Rewriting the entire codebase anytime I learn that I was doing something wrong.

Rewriting entire functions whenever I see that my coworker coded bullshit on the fly.

In a nutshell, I should stop trying to rewrite everything!

Yeah well I was in a position similar to you, rewriting every stupid code that my stupid co-worker wrote. Then I said, "fuck this and fuck him"... Weeks later, every bug assigned to me, was caused by my stupid co-worker, so I've end up in the same shit

#2 is me whenever i work in a group