Alas, you can't gamble your company on getting a Terry Pratchett or J. J. Rowling -- or a Dan Brown. Those folks come along once a decade in the worldwide English language market. The overwhelming majority of works of English language fiction sell less than 100,000 copies (hardcover, ebook, and paperback, across the North American, and UK/Commonwealth markets, and in translation); indeed, many sell fewer than 10,000 copies.

Most folks have no idea how micro-targeted a niche business publishing is. The goal of a large publisher is to find a lot of these small fry and hope one or two of them will break through and make the big time; just one such author can float the rest of the midlist at a publisher for many years, raising the chance of another huge bestseller coming along.