I wish that I could be a one draft writer. That would make my writing go so much faster. With short works, I can get there, but not with books. Even though I pull stories out of that noise kicking and screaming, because I'm not as good at stories as I am about making stuff up, enough noise still accumulates that my novels teeter between incoherence and banality on those first drafts. The text flow often jumps, and sometimes jumps badly, so much so that any reader, including myself, is challenged to figure out what in the world that I actually meant.
Drafts are all about hunting down and eliminating incoherence. I am literally making the text read smoothly as opposed to losing the reader at the next left turn that doesn't actually exist.
As I am an emergent writer, I also discover where I missed beats as I write. Sometimes these are simple things, like making sure that character do all their required actions, to major things, like realizing that I dropped a murder plot line. Noises exists in the plot just as surely as noise exists in the text.
After enough iterations, depending on which writing style and voice I've adopted, I'll have a novel. In my opinion, they are very nice. I am often surprised when I go back and reread what I've written. All that work pays off in satisfaction.