I once talked to a writer who told me that she read her novel over from the start on each day before she began writing again. If I did this, I would never write another word. When I think of my approach to writing, the word "headlong" comes to mind. I pitch forward, trying not to look back until I come to what I think is the end. Then I begin re-writing. I have an obsession with completing things. The doubt that would overtake me if I had to re-read my early drafts would be paralyzing. Here's a good article from The Guardian about the self-critic.