“The perfectionist is never satisfied. The perfectionist never says, "This is pretty good. I think I’ll just keep going."”

To the perfectionist, there is always room for improvement. The perfectionist call this humility. In reality, it is egotism. It is pride that makes us want to write a perfect script, paint a perfect painting, perform a perfect audition monologue.
Perfectionism is not a quest for the best. It is a pursuit of the worst in ourselves, the part that tells us that nothing we do will ever be good enough — that we should try again. No. We should not.
In Inspirations : Meditations from The Artist's Way (2001), Cameron extends the above statement with further remarks: Focused on process, our creative life retains a sense of adventure. Focused on product, the same creative life can feel foolish or barren. We inherit the obsession with product and the idea that art produces finished product from our consumer-oriented society. This focus creates a great deal of creative block.
The Artist's Way (1992)