The old adage is true — writing is rewriting. But it takes a kind of courage to confront your own awfulness (and you will be awful) and realize that, if you sleep on it, you can come back and bang at the thing some more, and it will be less awful. And then you sleep again, and bang even more, and you have something middling. Then you sleep some more, and bang, and you get something that is actually coherent. Hopefully when you are done you have a piece that reasonably approximates the music in your head. And some day, having done that for years, perhaps you will get something that is even better than the music in your head. Becoming a better writer means becoming a re-writer. But that first phase is so awful that most people don’t want any part.