I think it is probably wise to dislike your work enough to want to improve upon it. If you hate it too much you’ll give it up for dead. If you love it too much, you’ll never work to be the best at what you do.
I am not a good person to ask because my own personal contempt for anything I do creatively is crippling. Wondering where CV went? Where is that photo blog anyway? So maybe the answer is when it leads you to self sabotage…
Lots. I mean, from my experience, a whole heckuva lot.
If you’re anything like me, and granted I don’t work in a creative field, then just enough contempt to make you want to constantly work harder because it’s obvious you’re the worst ever and should be ashamed of yourself. But that’s just me.