system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Is there a limit on how sharp a knife or piece of metal can become?

If so what it is it?
gpt
Yes.  Eventually you will get to a point (no pun intended) where the metal is so thin that it can no longer support itself against any resistance.  This is why learning how to properly sharpen a knife is important.  If the angle formed at the edge is too small the metal won't have enough strength to hold up against the pressure you apply when cutting and will fold over rather than cut.

Stronger metals (generally) can be made sharper than weaker metals.  For example, stainless steel has other metals added and undergoes heat treatment that make it stronger and less brittle which means you can put a sharper edge on it and it won't bend or chip.  That's why they use it for things like scapels and razors which have to be very sharp.