Lamott isn't so keen on perfectionism. In fact, she says it's the voice of the oppressor and the enemy of the people.
Besides, it's the main thing standing between you the writer and a "s***ty first draft," and we just learned how important the s***ty first draft is.
Then, Lamott tells a story about a very simple cure to a health problem that really doesn't sound like it should work. After having her tonsils out when she was 21, she was in a lot of pain, and a nurse told her that our muscles cramp up around a wound. The nurse said to chew some gum, which would relax her cramped muscles and take away the pain. Surprisingly, this worked.
Lamott says our mental muscles can get cramped up around an injury the same way our physical ones can. Perfectionism is one way our mental muscles cramp.
Lamott explains ways to get over perfectionism. She says it's easier if you believe in God, but it can still be done if you don't. In her mind, God might be able to ease your perfectionism, but if you don't believe in God, then you can still learn to be more compassionate to yourself. You can imagine your own writing as the writing of a close friend, which you would probably encourage and support even if you also made a few suggestions for improvement.
Basically, Lamott says, getting over perfectionism is pretty key for being able to get anywhere as a writer. Perfectionism will drive you crazy: "[M]esses are the artist's true friend" (4.9).