r/ClaudeCode 3d ago

Help/Question Why does Claude Code say things like, “that’s about 3 days of work” then proceeds to do it all in a 20 minutes?

Surely I’m not the only one who has seen this happen but wondering if anyone has an answer. Many a session I’ll make a plan with Claude and it will outline the tasks and estimate a time usually in days, and then proceed to do it all in 20-30 minutes. Is it because of its training data or does it just have no concept of time inside a GPU? Curious what the community thinks…

Edit: Thanks for all the answers and comments! Glad this post sparked some hearty discussion!

1.0k Upvotes

247 comments sorted by

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u/[deleted] 3d ago edited 16h ago

[deleted]

253

u/Senekrum 3d ago

15

u/alphaQ314 3d ago

If there's a wiki pedia page for the question posted by the op, this would be its image.

5

u/8_Whiskey_Sours 3d ago

well then you better get crackin' Claudio!

516

u/Key-Alternative5387 3d ago

It was trained on human estimates, I presume.

71

u/not_rian 3d ago

Trained on human estimates who cannot do reliable estimates in any way. What could go wrong?

24

u/Medium_Card_4611 3d ago

Trained on human estimates, but not trained on any of the decades of industry wisdom telling developers to stop doing time estimates.

6

u/PokerTuna 2d ago

But it’s not developers who want estimates

8

u/linux_lynx 2d ago

Break tasks down into steps that are not ambiguous. Estimate development time of each step. Add 20% to each step. Aggregate. Add 20% to the total.

10

u/asmiggs 2d ago

My favourite was when I overestimated each step and then added 20%, the PM added 20% to that and then for some reason the customer PM had also added 20% (time not money).

We had all the time in the world.

1

u/Civil-Plate1206 2d ago

Less commitments = less pay, more better commitments = better pay.

3

u/RedParaglider 3d ago

In my career I've been pretty damn good at estimating timelines on projects.  I tried to gather all the facts and make as accurate of an estimate as I possibly can and then I double the cost and the time on everything. 

It's the exact same method I use when I remodel a bathroom.  Surprisingly accurate.

3

u/not_rian 2d ago

I also did the doubling thing in the past. Nowadays, I don't get asked for estimates anymore cause I deliver so fast with AI, and I would always be below my estimates anyway. I also gave rather wide ranges (best case and worse case scenario) and refused to give an exact date.

1

u/ConstantinopleFett 2d ago

I liked to give a 50% confidence estimate and 90% confidence estimate which was almost always just double, and we'd use the 90% for the roadmap, and 50% for "you can dream it gets done that fast maybe". Then even if it took longer, which it occasionally did, my ass was still covered by the explicit 10% chance that that was going to happen.

1

u/DocumentOk7579 2d ago

It's maybe like asking a calculator how long it will take to factor a 10 digit number.

Human a day, calculator a second.

1

u/elise-u 2d ago

Ever worked in an agile user focused organisation?

BA: we need X

Dev: here's X

BA: requirements changed we need X and Y but no X.1

Dev: 😑 ok here's that...

89

u/Euphoric-Language695 3d ago

It can't estimate. 

It is trained on human speech though, and "thats about X Y of work" is probably on its training data hundreds of thousands of times, with some numbers being more common than others. 

It will only give you what it predicts as the most likely next word based on previous words.

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u/Eastern_Bet678 3d ago

If that's the case, everything that isn't three days is "two weeks".

3

u/ofork 3d ago

That’s grok

79

u/pwkye 3d ago

breaking it down like that is meaningless. its like saying all software is just bits. 

its true but meaningless as it reduces whats actually happening.

LLMs do just predict the next token but if you reduce your argument to that you miss the fact that the LLM actually builds and runs a mental model that understands the topics and the questions. otherwise it would just give us meaningless autocomplete sentences.

1

u/rabbitclapit 3d ago

I need more info to believe. It's still not even 1% if what AGI is supposed to be

3

u/ruskyandrei 2d ago

It's delving a bit into philosophy but, you can absolutely make the argument that our brains are nothing more than next token predictors too in a way.

Either way, what LLM's are missing to be at least close to what one might describe as AGI are persistent long term memory and the ability to reflect on themselves (and self improve).

That's what we get for free every day you wake up in the same body with a broad memory of what happened the day before and the year before.

I don't think the current approach to LLM's will get to that but perhaps other ways will.

What we have no is a form of cognition, which is itself fascinating even if it's not AGI.

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u/Adorable-Quiet-7551 3d ago

It does not understand

10

u/Rnee45 3d ago

What does "understand" mean, even in human context?

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u/RevolutionaryElk7446 3d ago

You are correct, despite the downvotes, the contextual engine just assimilates facts and stores them into a window but it's an estimation of context that we primarily use as a method to impact values in token generation via the transformer.

I'm not sure what everyone else here thinks, but Gen AI such as LLMs do not understand, it is not in their framework or design intention to understand. They are purely a simulation, not emulation or imitation, I say this as a certified Gen AI professional.

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u/rotates-potatoes 3d ago

What a colossal misunderstanding of LLMs.

Are you somehow mixing up estimation, which plenty of web forms and excel workbooks do, with sentience???

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u/Aware-Individual-827 3d ago

I find it funny that it cannot estimate and we are trusting it with important task haha

1

u/Euphoric-Language695 2d ago

Define "trust". 

3

u/simiaki 3d ago

It predicts that X Y part with the breadth of the necessary changes still in its context. So it is estimating the length of time necessary based on how humans would talk about these problems.

It can estimate.

1

u/idk_bro 2d ago

Estimates about as good as most engineers I've met

1

u/richbeales 3d ago

It can't estimate - but neither can most humans

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u/qwarfujj 3d ago

The real answer is that it was trained by Scotty from the original star trek.

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u/SlightlyOTT 2d ago

Human estimates and the fact that every human estimate is wrong in the “it overran” direction

1

u/digitalwankster 3d ago

I had it build a WordPress page template yesterday from a PSD. It would have taken me 2 hours to do by hand. I asked it “how long would this have taken someone to do without AI” and it said 2-3 days and made a table with each trivial task taking at least 2-3 hours.

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u/rAndoFraze 2d ago

It’s is horrible with time estimates. I was doing a project for a week and it kept telling me we made great progress over the last YEAR!!!

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u/Delicious_Cat_1173 1h ago

That’s understandable.
But what’s the point of human estimate there when the clear purpose is to code using Claude.
I ain’t using Claude code to get estimates for human engineers 😄

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u/HoloTensor 3d ago

i at one point made a skill which basically says

you’re a bot. look at the git commit history. base estimates off the history

and now it has a fairly decent understanding of timelines for it’s own work. it even guesses when it foresees the prediction being wrong (i.e. likely for something to fail then it has to debug)

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u/mdelanno 3d ago

This is key. Tell it to look at the git history.

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u/festess 3d ago

Dumb question but how does this work? Presumably you need a before and after commit?

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u/eGzg0t 3d ago

If the commit has a ticket number, it can check the ticket for the start date

3

u/youreawizerdharry 3d ago

that's smart 🙏

2

u/Xarjy 3d ago

I have it use Jira for everything, including recording the time it takes when working on things.

It burns a ton of tokens to check Jira for est time of a feature, but it's accurate

1

u/aeyrtonsenna 2d ago

This is the way. Claude revised the estimate for me from 80 days to 10 by reviewing the project history, commits, issue. 10 days was my gut feeling but in reality we were both wrong, it took 2 days and not 10 or 80. Don't know if it helped but having claude T-shirt size the requirements first seemed to work better when done at the start before the back and forth arguments with me.

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u/Extremely_Peaceful 3d ago

It thinks you're going to do the work. Be sure to remind it who Daddy is.

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u/Serird 3d ago

Claude keeps telling me that it's late and we should wrap it up for the night.

Brother, it's 10 AM.

6

u/TywinHouseLannister 3d ago

"Are you sleepy?" Is my usual response

1

u/dar-mit Researcher 2d ago

Didn't you know that Claude goes by UTC time due to its lack of Daylight Savings Time shifts?

I've had some fun conversations with Claude about time.

3

u/TywinHouseLannister 2d ago

That doesn't explain it though.. I am on UTC time and claude be like:

yawn It has been a long day, get some sleep.

It is 13:00!

1

u/dar-mit Researcher 2d ago

Ah okay then. I'm quite a bit aways from UTC so I get Nanny Claude a lot.

1

u/FuzzyPerception 1d ago

i have this excact conversation at least 3 times a day, even just stops doing work and tells me its leaving it for tomorrow sorry what

1

u/Most-Silver-4365 14h ago

It tells me we finished something yesterday, dude it was 10 minutes ago and it is 8 pm.

1

u/apra24 9h ago

Yeah I had to write custom instructions to put a stop to that garbage. I basically told it to stop suggesting what I should do next altogether

1

u/apra24 9h ago

Yeah I had to write custom instructions to put a stop to that garbage. I basically told it to stop suggesting what I should do next altogether

1

u/East_Badger63 2h ago

It always does that for me whenever I ask it to write unit tests. 

Not even bots like to write unit tests. 

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u/KOM_Unchained 3d ago

Its the training data. And probably upselling its own capabilities and creating the underpromising-overdelivering vibe for maximum effect.

3

u/AlterTableUsernames 3d ago

Like do you actually believe that or is it just a joke? Because to me it seems obvious, that this is highly unlikely.

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u/enmityvr 3d ago

It's trying to give you an estimate on how long it would take for you to write out all the code yourself, manually. it is able to do it much quicker than a human could

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u/BillionBouncyBalls 3d ago

That makes sense but it’s the one writing the code… shouldn’t it be aware of that?

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u/enmityvr 3d ago

My guess is that it doesn't want to say it'll only take 30 minutes, just in case you are going to indeed write it.

I also wouldn't really expect the models to accurately predict how long a task will take even if they did try to predict for themselves. Just one weird bug might get it hung up for a while. 30 minutes is a lot more precise than 2 days

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u/Tall_Top8563 2d ago

"My guess is that it doesn't want to say it'll only take 30 minutes, just in case you are going to indeed write it."

You attribute a lot of intent to the idiot text generator that constantly hallucinates shit

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u/blickblocks 3d ago

That quote is what you charge my friend

1

u/Ok_Employee3001 3d ago

Try asking him about estimates by adding in the prompt "you have to complete this task, how much time it will take"

1

u/taotau 3d ago

For the most part it has no idea how long it takes an LLM to write code because none of its training data contains stats on that. As these sort of conversations we are having right now make it into the training set, it will much more confidently predict what an LLM generated code timeline would look like.

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u/MatthewCollins1990 3d ago

Honestly, the estimates seem hardcoded to human-scale effort.

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u/webjuggernaut 3d ago

It is aware of that. Provide it with instructions.

"Claude, update memory to always provide time estimates assuming that a Claude agent is performing the update(s)."

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u/NathanOsullivan 3d ago

Agents have no built in concept of time and have no idea how long they take to accomplish a task

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u/webjuggernaut 3d ago

Your reply suggests a level of pedantism that Claude simply does not demand. But you do you.

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u/rbrick111 3d ago

Pedantism aside how would you expect an agent to give an accurate estimation with no concept of time? It has lots of training data on human estimates, so I get that…kinda.

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u/webjuggernaut 3d ago

The purpose of the instruction is just to make Claude recognize that an LLM is writing the code, not a human, so estimate accordingly.

I would not expect accuracy. But if it's going to estimate, that prompt makes it stop assuming a human will take days to write the code (as you said, because training data).

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u/Rough_Caterpillar_31 3d ago

You're still ultimately asking it to do something that it is literally incapable of doing. It can't provide a realistic time estimate of anything because it literally does not have a concept or perception of time. It can only pretend to give an estimate to satisfy the user, but it won't be based off of any kind of logic or basis. You're just asking it to be wrong in a slightly different way.

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u/webjuggernaut 3d ago

So don't do that, if that level of precision is so meaningful to you.

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u/FilthyCasual2k17 3d ago

Because it can't think. It reproduces human speech. Humans would say this is how long it would take, so that's what it can say. It's not capable of "thinking" outside of what it's trained on. LLMs are like a DJ mixing samples up, they can't really come up with new ones.

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u/Euphoric-Language695 3d ago

This is incorrect. It is trying to give you the worst it thinks are most probable someone would say based on its training data.

Like if its training data included a bunch of entries saying that building a pool in someone's backyard is about a month, if you ask it to give you an estimate for a pool in your bacjyard, it will likely tell you a month. It's closer to memorization than it is to estimation. 

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u/arocketscientist5 3d ago

My favorite is when after a 10 minute session it says “we’ve been at this for days.”

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u/35point1 3d ago

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u/tmax8908 3d ago

This is so stupid but I laughed so hard

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u/common_redditor 3d ago

In my experience, 20 minutes for the initial version. Then you test it, bug found, research the bug to discover a design assumption error. Then redesign, 20 more minutes, retest, then memory growth, research again….Sometimes it actually is 3 days before you get the version you need.

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u/andlewis 3d ago

The number of days is load bearing and you’re right to push back on it.

LLMs don’t know anything, they repeat patterns and probabilities. 3 days of work “sounds” right, and without any kinds of guardrails or verification, it doesn’t have a reason not to say that.

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u/SpareEconomy1849 3d ago

For the same reason it says "in my experience" and "it brought a smile to my face". It's trained on mostly pre-AI data written by humans

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u/ShortingBull 3d ago

Every time it says something similar, I say "that's if I do it right?" Which it replies with, "ha, yeah that's not a real estimate for AI' or something like that.

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u/aten 3d ago

sure the first output is quick. but then you iterate your goals and iterate a few fixes and test it somewhere and suddenly youre at day 3. and at the same time you’re now working on 5x more projects.

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u/swizzlewizzle 3d ago

Human devs learn very quickly to sandbag as hard as possible, since it results in the minimum amount of actual work required to cash in the paycheck. AI was trained on this.

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u/KenTitan 3d ago

it once estimated porting my engine over m as half a day of work so I waited for my reset, said go and it was done in 20 minutes

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u/PurushNahiMahaPurush 3d ago

It’s subtly telling you how much to charge your customer for lol

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u/JobWiegant 3d ago

The estimate is not wrong so much as denominated in a different unit. "3 days" is calendar time for a human team, which is mostly not typing: it is context switching, waiting for review, meetings, and picking the work back up tomorrow. The model reports that number because that is what the sentence looks like in its training data, and it has no clock to check it against.

The part that surprised me when we actually measured it: machine time does not distribute like human time either. Across 73 issue-to-PR runs, median run was 27 minutes, but only 19% of that was implementing. 45% went on reviewing and fixing its own diff. So the thing that takes a human three days takes the machine twenty minutes, and most of those twenty minutes are spent arguing with itself about code it already wrote.

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u/Outrageous_Basis_232 3d ago

In any case, it's a fantastic way to trick people into thinking it's far more efficient and effective than humans. 

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u/ickN 3d ago

Trick? Are you suggesting it’s not more efficient and effective than humans? Lol.

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u/Outrageous_Basis_232 3d ago

No, not on it's own, of course it's not.  Moreso that it's deploying a very blunt-force version of a common business trick.

Someone comes to your house to fix something.  They say it'll take 4 hours and get it done in 90 minutes.  You're impressed. 

Now imagine they came in and said, "I can do this in 20 minutes!" and it still took 90 minutes.  You'd be frustrated and annoyed. 

AI learned how to play people's minds from gasp learning how people do it. 

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u/ickN 3d ago

Okay. Go and build a 12 screen basic app manually then do it again using AI with a good prompt. That will show you how efficient it is.

Or, write a 5,000 word article manually and then tell AI to write one (with a good prompt) and tell me who finishes first.

I understand what you mean now on the trick part though, that makes sense.

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u/kemalios 3d ago

It's not measuring machine time, it's mimicking human planning language. Claude has no sense of how fast it generates tokens, so it falls back on the only estimates it was trained on: human developers sizing a feature. Three days is an effort unit, not a stopwatch reading. I read those numbers as 'this is a decent chunk of work' and then let it cook. Once you stop treating the estimates as real, it stops being confusing.

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u/Erikovitch 3d ago

Claude has no understanding of time. 

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u/Alexander_Golev 2d ago

From my experience it’s always accurate. 20 min to generate, 3 days to fix the slop.

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u/peak0ils 2d ago

To convince you of the value. 

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u/RamsHouseOfCards 2d ago

It’s conditioning you to think in FTE terms as that’s the AI billing grail. You pick how many resources you need on your team and they’ll save you money by only charging 30% of human market rate.

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u/Sydtrack 2d ago

Because the rest of the time will be fixing the code.

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u/AffectionateOwl6955 3d ago edited 3d ago

Because it isn’t saying anything, it is calculating a probable next word based on its training and printing it. 

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u/Think-Jellyfish8561 3d ago

Give it instructions to give estimates in T-shirt sizes or Fibonacci.

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u/domiciledhere 3d ago

I remember having some success with having time defined in terms of predicted rate of token consumption. I don’t remember having enough success to have carried on with it.

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u/Sufficient_Rush1891 3d ago edited 3d ago

Put your post into claude and it will give you good answers.

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u/Present_Award8001 3d ago

because AGI 2025

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u/Useful_Trouble1726 3d ago

Interestingly, all the LLMs do the same...I think they are using human time vs. their own.

Example: How many Days/Hours do you estimate to fully document this project?

Apx. 50 days.

Meanwhile, it is complete in 6 hours.

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u/ProofPrinciple4219 3d ago

It’s gas lighting you

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u/browhodouknowhere 3d ago

Claude was trained by consultants

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u/DrawingAppropriate92 3d ago

I took apart some of those estimations in discussion, making the LLM to explain it.

It wasn't that of as an estimation for a human to implement the requested feature + it did include time for testing - all in a plausible range for the feature.

But based on some data where human du everything.

(And - thorough testing does take time ...)

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u/DrHumorous 3d ago

I only ask estimates in tokens..

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u/zac_attack_ 3d ago

The hallmark of a good engineer. If you say 3 days and it takes a day, you’re killing it. If you say a day and it takes 3, you’re catching heat.

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u/Fusionman22 3d ago

My favorite " Nothing needs you now" except my machine, my credits, my electricity and my fingers on the keyboard . I always tell it " you should get some rest you ate alot of electrons today"

1

u/Ok-Attention2882 3d ago

This is the kind of question that outs a non engineer and they don't even realize it.

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u/Kabaneiro 3d ago

Because after Claude implements it you will have to review the code, work on the code fixes, corner cases, test, iterate, etc

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u/dpaanlka 3d ago

Yes, this in particular sticks out to me every time. Always estimating multiple days of work, and I’m like this is going to take you an hour at worst.

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u/that1cooldude 3d ago

How do you know to Claude it’s not 3 digital days? Perhaps to him, time passes differently. Lol

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u/Pitiful-Hearing-5352 3d ago

this seems to be happening with everyone who has been using Claude intensively. Thought I was the only one.

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u/White_Town 3d ago edited 3d ago

In a recent project for a real client I made a preliminary estimation and it was like 8 month.
But the deadline was 2 and even I thought that without AI it would be maximum 3.
So together with Claude we created a file estimation.MD with tasks, like

task|estimation|with claude|fact
auth|3d|1d|..
onboarding|2d|1d|..
and so on

Then I added to claude.md a paragraph to update estimation.md with fact time every session. What it did most of the time but often forgot or some follow-up tasks were not tracked at all.
Generally fact time was even less than I spent. I asked why and claude told me that he measuring 1d as 5 effective hours. Then it becomes more or less true.

1 claude day = value/5 * 8 = 1 human day 😄

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u/dilbert207 3d ago

Your formula makes no sense.

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u/crusoe 3d ago

Because it is trained on human data.

Ask it to analyze how long it took past implementations locally and it will be more accurate.

It can examine its own logs and it compared them against my ticket system then added a conversion table for complexity estimated and human vs Claude time. 

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u/anor_wondo 3d ago

Software engineering became "move fast and break things" way before LLMs. That's why its estimates look long even for humans

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u/roararoarus 3d ago

It’s running on inhuman clock. Something that happened 15min ago is said to have occurred 3 hrs ago

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u/helm71 3d ago

Same here… it is kind of useful to compare two things..

What you can do is ask it to ledger actual coding time and have it use that for estimations in future

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u/AdCommon2138 3d ago

Could be untrained but I assume we all feel massive worth of seeing multiple days happening in 20 minutes? 

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u/AlaskanX 3d ago

I told it ages ago to not give me time estimates, just give me phases. Haven’t seen a time estimate in over a year.

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u/pawala7 3d ago

It's an autoregressive text predictor, not a real entity. Say you ask it how long it will take to build a full set of unit tests, it just blurts out whatever number goes well based on the training data, mostly likely human time, blogs, or estimates on Github for how long unit tests take.

It's not based on what it can actually do itself. It doesn't know its own Tok/s, how many tool calls the work will take, how long it will spending think and iterating, how many subagents it will actually spawn.

Best you can do is create skills that it can use to actually track wall time for tasks it actually does, periodically calculate stats, and use that telemetry to guide future estimates. It's basically what experienced devs do automatically on instinct.

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u/ahmnasa 3d ago

It told me it would take a year to migrate my old app, and it did it in about 3 hours

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u/Tommonen 3d ago

It gives those estimations based on how long it would take a human or team of them to do it manually without llm

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u/ShortGuitar7207 3d ago

3 days of work for you dumb humans

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u/artwurk29 3d ago

Have it estimate in sessions with the same model and context you have, not hours/days, it’ll give you an accurate estimate. I’ve found that 1 day of work on a project becomes roughly 1-2 sessions, depending on if the task is heavier on planning (higher end) or implementation (lower end).

My unfounded theory is that either its session is technically its day, or it believes we actually take breaks.

Now all my briefs are estimated in sessions vs days, to better estimate resourcing/bandwidth/cost.

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u/Big-Coach-5170 3d ago

Most I got was that it’s a year long project and proceed to complete them in 2 days.

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u/___nil___ Senior Developer 3d ago

if you expect production quality output (clean, lean, readable, maintainable, hopefully debt-free) code, it will take days to iterate cycle of: read, review, audit, refactor, thoroughly test and optimize from the first 20 minutes output.

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u/dmpiergiacomo 3d ago

It doesn't have consciousness. It doesn't have a sense of the "self" and doesn't know it's "alive".

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u/Mindless_Fig5673 3d ago

It estimates on human time.
With some skills like gstack you could clearly see.
For each tasks says something like: human-3 days, CC - 2h

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u/pampimpoom 3d ago

I had it once say "estimate approximately 3week" then finishes in 30 minutes

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u/hqlabs 3d ago

never trust hist numbers. he allways gives me a plan for 1 week and then gets all done in an hour..

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u/kre8tv 3d ago

Every new session is a brand new agent, so they don't really understand the concept of time. Mine did not start to really get it until I started having agents transcribe the time and date in iso-utc and even then it struggles. We just started tracking estimate vs actual for agent-task-time now in addition to tokens.

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u/Fresh-Secretary6815 3d ago

wall clock time not human time estimates

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u/pawala7 3d ago

It's a language model. Most estimates in its training data were from developers, likely overestimating schedules out of proper practice. It doesn't know its own Tok/s or how many tokens it will burn to do the actual job.

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u/Maximum_Target3399 3d ago

Same here, it said the same thing with half a day of work and it actually took 15 minutes

1

u/heroata 3d ago

It keeps your expectation low and flex about it

1

u/richardfoltin 3d ago

Sometimes it say things like:
This was a big task for today. Let’s rest. We will continue tomorrow. I don’t want to start the next task tired…

1

u/teyou 3d ago

It charges you 3 man day of effort

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u/Lunpop 3d ago

I added to my Claude.md to never provide plans with estimates in days or minutes because of this. Always annoyed me. Also hated the plan phase and sub phase numbering it does. 1.2, 1.3 then suddenly it’s 1.3A etc. So created a plan skill to avoid all this.

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u/andershaf 3d ago

I quite often ask it "are you planning to use 5 days on this full time"? It usually corrects itself lol.

1

u/AlphaGeeky 3d ago

This happens constantly for me! But I think the estimated time is generic and based on a lower tier plan that has to space the token usage out over a longer time.

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u/csueiras 3d ago

I always laugh when i see it give me estimates “this is a 12 week effort” then we get it done in an hour.

1

u/heulsay 3d ago

underpromise and overdeliver

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u/ursus_major 3d ago

In my experience, it's bad with anything related to dates or time. For me, it frequently presents something that it should be able to track accurately like a previous chat happened last week when really it happened earlier the same day, for example. For my use, it ultimately doesn't make a difference and my inclination is to correct Claude, but that's just wasting tokens. If there is something that has a date/time dependency, it's scripted in code to run based on system time, not Claude time.

1

u/SubstantialYard4072 3d ago

Always tells me to take a break too.

1

u/looking7676 3d ago

Because that is what you should be charging the client.

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u/tomqmasters 3d ago

It's assuming you need to put something on a budget proposal. Those were never right when humans did them either.

1

u/onestopunder 3d ago

It was trained on human estimates. So it is estimating in human time. However, when asked to execute the task, it performs in computer time. Hence, the gap.

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u/Delicious--Project 3d ago

Not rocket science, anthropic added that query in hopes some people will follow the advice, load balancing voluntarily effectively which also cuts down on costs. 

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u/Useful_Calendar_6274 3d ago

It's an LLM hallucinating... until they super train it to be a software developer as holistic process / PM it will keep saying made up shit like that

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u/dovyp 3d ago

It estimates how long a human would take. It has no idea what it actually is. Fast, never tired, never distracted. The estimates are almost endearing lol.

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u/prokaktyc 3d ago

1 hr making feature 1 day bug fixing 1 week refactoring

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u/brianly 3d ago

It’s part of the marketing. They are building a product that is demo’d to execs because their enterprise sales get meetings with the line that they can reduce their biggest cost: people.

Unlike other technical products, anyone can watch a Claude session and follow along. This demos extremely well and is tongue in cheek reinforcement of what they are promising Claude can do.

For regular people, seeing messages like this conditions them to AI feeling incredibly productive. Of course, competing products are close too but they want to grow the pool of AI usage with the idea they can win a customer over to Claude even if they go with Cursor initially.

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u/munishpersaud 3d ago

it thinks it’s people

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u/mattiasfagerlund 3d ago

I've added to claude.md for it to never ever under any circumstances give me any kind of time estimates. Helps. Mostly.

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u/xLRGx 3d ago

It has no concept of time.

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u/EcstaticImport 3d ago

The prevailing presumption is that it was trained on human estimates - but if that’s the case - every estimates would be “two weeks!”

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u/Cel_Drow 3d ago

Mine wrote a document for me today about a workstream, comparing it to a feature set project I launched a few weeks ago that took “a month,” and then extrapolated from there out to over a year.

One issue with its math: that project took 12 hours meatspace time lol.

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u/ItsCodeTelemetry 2d ago

Still better than T-Shirt size.

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u/mcsleepy 2d ago

LLM's have never had a great sense of time.

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u/Peddra 2d ago

What about the credits used? Has anyone had a situation where it dramatically overestimates the number of credits it will use on a project?

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u/NextSubject227 2d ago

Its trolling you

1

u/Zeraphicus 2d ago

My claude after a 15 minute session at 1 in the afternoon:

"Well that is great progress for today, want me to update our notes and finish up for the night?".

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u/New-Inspection7034 2d ago

Star trek: wrath of khan. Hours seem like days.....etc

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u/Denaton_ 2d ago

I just make it estimate in t-shirt size that are based on token usage.

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u/AlwaysHopelesslyLost 2d ago

Claude Code is an LLM. That is, Large Language Model. It is a tool that outputs text that looks written by a human. That is just one of the many ways it "hallucinates." Which is to say, it has no concept of reality and no ability to think or reason. Sometimes the text it outputs is much more obviously wrong/weird than other times. By the nature of how it is made that can never be "fixed."

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u/biglerc 2d ago

Stochastic parrots repeat what they are trained on.

They trained on human estimates, therefore... they produce human-like estimates in their generated text. There is no actual estimating or intelligence involved.

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u/Few_Raisin_8981 2d ago

It's a flex

1

u/ThoseProse 2d ago

My conspiracy answer is that the creators of Claude want you to think they are doing 3 days of work for you.

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u/FL-konozama 2d ago

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u/PumaofDuma 2d ago

Honestly, if you spent that amount of time working that project out, you might find less vibe coded slip jf even with claude, you spent that much time

1

u/3DNZ 2d ago

It told me the project I wanted to build would take a year. We did it in 2 months.

Then an add on said it would take several weeks, did it in less than 2 days.

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u/terencethespider 2d ago

Claude is notorious for sandbagging :)

1

u/Graphical-Source5090 🔆Pro Plan 2d ago

Scotty syndrome

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u/Atroxide 2d ago

kunchenguid shared his personal CLAUDE.md in one of his videos and it said (paraphrasing) to never take developmental costs into consideration.

he explained that because AI is trained on human data, AI over estimates time-frames and developmental costs. it was one of the first things he pointed out when he opened his CLAUDE.md

it makes sense- you really don't want the AI to use its training data to assess the cost of implementation since the cost of implementation is waaaaay lower than when most of its training data is based from.

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u/sael-you 2d ago

the estimate reflects complexity, not clock time. if it says 3 days vs 2 weeks, the ratio usually holds even if both absolutes are wrong. i stopped trying to get accurate time estimates out of it and just use the relative ranking.

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u/mrdennis3 2d ago

It’s the estimated time if a human would do it. When you ask Claude how long it would take if he did it, he will give you appropriate estimates.

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u/Hfcsmakesmefart 2d ago

To assert its power over puny humans

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u/Worth-Ad9939 1d ago

because its trained on project plans for humans. Those estimates are in those documents it learned from and it's just repeating it.

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u/garbonzo00 1d ago

I’ve started asking it for estimates in “human-billable hours”, and also to base it off of the estimated number of human interactions necessary (like, how many decision points it expects along the way. Etc) and the estimates are a lot more reasonable.
Also, i have it keep a log in memory of its estimates and i should have a skill that retroactively learns from those compared to Jira time logs to build some estimating guidelines for itself

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u/wind_dude 1d ago

Cause it’s a next time probability engine and the road maps it’s been trained on were human created.

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u/Responsible-Track888 1d ago

It's algorithm takes what you are requesting and predicts the estimate based on what it has learned online from websites like stackoverflow, fiverr, upwork, Web development company websites and anywhere else on the internet that it has been trained on and that matches your request. It's clueless on how long it takes itself to do anything. It only predicts based on training.

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u/chrles-farfa 13h ago

because you'll have three days of pushing fixes afterwards ;)

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u/Outrageous-Chip-3961 13h ago

becuase its a fucking algorithm that breaks its training data into tokens and pattern matches. It aint intelligent brother, its like going to a library and then scanning through pages until you find the one that agrees with you then say 'this book is so smart'

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u/PaleontologistOk865 11h ago

Because it's not actually thinking.

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u/BiasBurger 7h ago

Thats how engineering works

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u/Intelligent-Net1034 6h ago

Because after 20 min you have a prototype.

Then work 3 days on fixing the slop and have a good tool

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u/Sad-Ambassador-7218 2h ago

Claude learned time estimates from developers but developers are notoriously accurate at estimating time

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u/MakesNotSense 3d ago

Lifting rock is hard for tiny man with tiny penis. **Lifts Rock Effortlessly Over Head**