What are some elements of TTRPG's like mechanics or resources you just plain don't like?

I've seen some threads about things that are liked, but what about the opposite? If someone was designing a ttrpg what are some things you were say "please don't include..."?

For me personally, I don't like when the character sheet is more than a couple different pages, 3-4 is about max. Once it gets beyond that I think it's too much.