I have this senior teammate that has been in a field for 11 years. The mistakes he makes are such a beginner level, like, commenting-out 20 lines of code without 'why', over-complicating block of code/not seeing easier solution, premature abstraction, not writing tests etc. I know he feels embarrassed sometimes when I write a lot of comments in PR, but also it feels like he's appreciative. Such a weird mix.