According to Ha Jin, the author of Waiting and War Trash among other books, there is something to be said for taking your time:
Be patient. Patience is everything.
I write everyday. When I have a large amount of time, in the summer, I can write a draft of a book and then when I teach I can edit and revise the book. Even though I work everyday, it doesn’t mean I write everyday. It’s impossible. It takes such a long time. It’s far from finished once you have a rough draft. Sometimes you just waste weeks and months. It happened to me a few times. I wrote 18 pages and realized it was terrible and had to start again. That’s why patience is everything.