I've talked to some aspiring novelists who wondered why no one wanted to buy the 1st draft of their original, brilliant opus--that hasn't been edited. O_o When I wrote my first novel, I thought it was very good--but it wasn't!
The truth is that it doesn't matter if you've sold millions of books or none at all, we all should edit our work. Anyone can make mistakes. No 1st draft is infallible.
I'm sure you've heard it a thousand times, but after you've written your 1st draft, let it sit for a while. I prefer to allow mine to sit for about a month, but that varies amongst writers and everyone has their own suggestions on that. While it's sitting you should work on something else.
Stephen King mentioned a funny anecdote in his writing/editing advice book, ON WRITING. If you're a writer, you need to read it. The anecdote detailed how his professor proofread something for him and instead of writing about pheasant hunting, he had written peasant hunting. :-) It was funny, but no one wants to make mistakes in their writing.
I didn't detail my editing process because I'm always changing it. When I sell a novel instead of short stories, then I'll be more willing to share a stable process. ;-)
So, if you ever think about not taking the time to edit, just think about what Blanche (Golden Girls) did when she decided to write her "brilliant" novel:
