But Paizo cannot keep releasing the same books again and again. He meant books will be getting more and more specific. Maybe players like to know there is a source book carefully detailing a small and far away area of Golarion, but not as many people will buy that book, most people buy a few books they feel are the most important. Then Paizo will be making less money from what they publish, and as understanding and nice to the hobby and the gamers as they are (no sarcasm here), things will have to change.
Paizo isn't expecting to make loads of bucks like WoTc. Heavy Pathfinder fans are not the same as heavy D&D fans. This is what Paizo has hit on and it's worked for them. WoTc tries to tell it's people when they are ready for a new edition while Paizo does not. Paizo seems to be working under the impression that if it works then it doesn't need to be fixed. Another one of their big success stories is the Pathfinder Society. It's living Golarion that caters to a lot of players and is always coming out with new adventures. I'm sure they look at their figures on a regular basis and if the numbers don't seem to fall drastically then they assume what they are doing is working and go with it until those numbers do fall.