A quote from my Writing the First Draft folder:
"Anyone can do the rough draft of a novel and it probably won’t look much worse than the first draft of any great novel you care to name. The difference between “anyone” and a serious writer is rewriting, rewriting and more rewriting . . . the serious writer reads the words with cautious, yet growing elation . . .
"Good rewriting demands easy, unhurried tinkering with words. Each unsuccessful try eliminates another wrong solution and leads you to the right one. I can’t emphasize too strongly how important this is, the fact that writing leads to writing, that failed attempts lead to eventual success, that the solution to a rewriting problem is made up of all the attempts that led nowhere.
The trouble is that when you’re just beginning to write, you may believe that words committed to paper are sacred, fixed, immutable. But you’re not dealing with a finished, printed, copyrighted book, only with an idea, a pile of words that will change many times before they take shape as a book."