Let's put it this way: if you are a novelist, I think you start out with a 20 word idea, and you work at it and you wind up with a 200,000 word novel. We, picture-book people, or at least I, start out with 200,000 words and I reduce it to 20.
I have a great interest in a number of things, perhaps too many. I admire people who seem to concentrate on only one fixed discipline to the exclusion of almost everything else.
American Gods is about 200,000 words long, and I'm sure there are words that are simply in there 'cause I like them. I know I couldn't justify each and every one of them.