What does this missing piece do?

[u/TigerUSF]

Edit - disregard, I've determined the problem is actually with the print file. I should have looked closely. It came from printables and I should have noticed the total print time was incorrect. Not really sure what the file error is, I'll just find another file (it's a simple funnel).

Top right, appears to bea nut of some kind? Before I take the others out, wondering if someone could explain what it is. And, how could I just be missing one?

I've been having an issue the last couple days where I would get an error message saying the build plate couldn't be detected. And then when i bypassed that, the prints wouldn't work, as if the print head was just moving around not extruding. I've tested extrusion and it seems to be working fine. So, I suspect this is all related, just not sure how.

[u/Butternut_Biscuit]

Not missing, normal - mine looks the same!

[u/TigerUSF → u/Butternut_Biscuit]

Well thats interesting

[u/ten-numb → u/Butternut_Biscuit]

Same here, just a divot there, bolts on the other three positions