Or is it? Question: What bestselling children's series had an entry that was new during the third quarter of 2003, but did not have a corresponding entry during the third quarter of 2004? This is not just that single book driving sales, either; books of this naturethat is, fictiontend to drive a great deal of coordinate sales, particularly starting about three weeks after initial release. For whatever reason, nonfiction bestsellers have a less-predictable pattern of getting their purchasers back into bookstores to buy more after they've finished the bestseller; and it's not just "series sales," either, as the first Harry Potter book had a substantial follow-on before the second book was released.
Perhaps what this really points out is that quality, high-end work that is also successful in the marketplace lifts more boats than does shoddy work that is nonetheless successful in the marketplace; but that's for another time.