The Facebook motto, “Done is better than perfect” is something to think about. Creative types learn this early, or if they don’t they never finish most, or even any, projects.
If you haven’t finished the job, you can’t even start to make it better. Until it’s roughly finished, you won’t truly know what needs to be fixed.
Yes, you do the best work you can as you go along. But accept, deep down, that it will probably need more work when you’re “finished.” A writer finishes a rough draft. Then she finishes draft number two. And on it goes until she finally has to say, “It’s the best I can at this time in my life.” And let it go, either off to hopefully get published or into that proverbial drawer never to be looked at again.
Striving for near-perfection is good. Expecting perfection is not good, because in almost all cases, it’s impossible.