Here's one reason why writing takes time:
There is a scenario, a single scene, with which I have been obsessed for years. I've had several gos at writing it: it's been a short story which I've tried at least twice to write and then abandoned. Somehow it kept coming out in a style that just wasn't me, really: too realist, somehow, with too much of a self-conscious moral which I didn't believe anyway, not really, it seemed somehow forced and fake. And the whole thing seemed thin, didn't have any real substance.
But it kept bugging me. Something about it must be important, after all... And I started to think that what was wrong was that the incident was not so much too flimsy as the tip of an iceberg of issues that the short story form hadn't been able to accommodate. It was, after all, I began to think, a scene from a novel.
So there it was in the first draft of my WIP. But there was still something wrong. It kind of floated, separate from the rest of the story, as a flashback, and again something wasn't gelling. And writing the second draft didn't change that. When I came to this third draft, I considered leaving it out altogether. It was just a darling that needed killing, after all, wasn't it? It didn't really move the plot along; it was just a nice little set piece with some good images which, let's face it, held up the action.
Yesterday morning I reached the section of the novel where it was included, and was prepared to cut it. But no, I couldn't: it just resonated too strongly for me. But then I had a problem deciding on the new order of events for the whole section, and I knew that this particular scene was at the heart of the problem. I made my decision but by the end of the day I didn't have that satisfied gut feeling you have when a piece of writing works. Today I came to type up the section, and I saw that indeed the order was wrong: that particular scene needed to come much nearer the beginning of the section.
And guess what? Moving it there, and the rewriting that that required, suddenly revealed to me the true meaning of the scene, a meaning that had previously been hidden from me, and which makes the scene after all utterly central to the novel...
It's because of this sort of thing that I always say: even when you cut things, always be prepared for the possibility that you'll need to put them back in...