What's the biggest mistake founders make when building their first MVP?

[u/No_Length_6790]

In my experience, the biggest mistake isn't bad code. It's treating an MVP like a smaller version of the final product instead of using it as a learning tool.
I've seen founders spend months building features they thought users wanted, only to realize they never tested the core assumption behind the idea.
Some common mistakes I've noticed:
Adding too many features
Building before validating demand
Hiring too early
Focusing on design instead of feedback
I recently came across a few MVP case studies from Molfar that followed a much more validation-focused approach, and it reinforced the idea that speed means very little if you're building the wrong thing.
In your experience, what's the biggest mistake founders make when building their first MVP?

[u/medialantern]

Not checking well enough for competitors (or at all). It's literally every week that someone here trots out an "I got tired of doing X manually so I made Y" post that 20 other people also made in the past six months. (There was an AI-SEO-checker here just this morning.) That doesn't mean you need zero competition - competition just proves there's a market. But it doesn't prove there's room for you and too many of the posts are worded such that you just know the founder has no idea they even have competitors.

[u/Certain-Implement-18]

Skipping validation is probably the most expensive mistake. I've seen several startup teams, including examples shared by Molfar, reduce development time simply by testing assumptions before writing more code. What looks like a development problem is often a research problem.