Each year, I serve as one of several manuscript editors for the Willamette Writers Conference. Writers pay a small fee and forward 20 pages of their work for editing and comments. These book beginnings typically run the gamut from great to horrendous and this year is no exception.
I'm finding that beyond certain difficulties with the language (some writers are excellent self-editors and some are not--it's an additional skill and not one that everybody has), the difference between the good ones and the less good has to do with how much the writing considers the story. You would think that would be self-evident, that writers would always consider the story but that's not the case. Just as many writers don't consider the reader as they're writing, many don't consider the story and what will best serve it.
If they did, they might well eliminate extraneous adjectives, meaningless dialog, excessive poetics, and abundant detail. I'm not advocating that every writer be a sparse writer--that's a matter of style and there's plenty of room for lots of different styles. But a good writer reads her own work and asks, does this detail, comment, fact, wrinkle in the plot, serve the story? Does the story need it to be all it can be?
Becoming familiar with what serves a story is best learned by reading great writing and noting how everything fits. In those pages, the story is well served.