Charlie Stross has commented that if he were self-publishing, he’d have to spend half or more of his time doing the parts of the publishing business that are marketing and distribution, not writing (even if he contracts out the editing, copyediting, etc.) He’s good at writing, and likes doing it. He’s not interested in being a marketing professional or distributor-to-bookstore-bureaucracies. And spending half his time Not Writing would mean he’d be putting out half as many books a year.
If you know anybody who does book publishing or editing, ask them about their slush pile. The 95% of the books that don’t get published traditionally because traditional book publishers don’t think it’ll be profitable to publish them have reasons the traditional publishers don’t think it’ll be profitable to publish them. Occasionally that’s because they don’t understand the book, or because it’s not the kind of book they know how to market, or because it’s not the kind of book that’ll be easy to sell in a store that’s designed to sell books printed on dead trees (e.g. it’s really dependent on internal hyperlinks or whatever), or because they’re already handling all the books in that subgenre that they think they’ll get shelf space for. But usually it’s because 90% of everything is crap, including 90% of the stuff that does get published, and reading everything that gets thrown over the transom by people who can’t get an agent is like spending your whole day at an Eye of Argon reading, by yourself.
