Bernard Malamud said, “First drafts are for learning what your novel or story is about. Revision is working with that knowledge to enlarge & enhance an idea, to reform it . . . .” This makes sense to me, as do other writer’s take on the first draft. For instance, Jennifer Egan describes her experience writing Look at Me this way:
It was a huge struggle. I’m not quite sure why I suffered to the degree I did while working on that book, but I do know that my work up to that point had been fairly conventional, and I didn’t know if anyone would accept this kind of book from me. It was almost as if I thought I’d be punished for it. I felt afraid as I worked on it. I thought it was terrible, that I was reaching too far.
You’ll find an article with other first draft stories over at The Millions.