If you think good work is somehow synonymous with perfect work, you are headed for big trouble. Art is human; error is human; ergo, art is error.
[Ansel] Adams was right: to require perfection is to invite paralysis. The pattern is predictable: as you see error in what you have done, you steer your work toward what you imagine you can do perfectly. You cling ever more tightly to what you already know you can do—away from risk and exploration, and possibly further from the work of your heart. You find reasons to procrastinate, since to not work is to not make mistakes. p. 30