Phase I -- the creation of the core rulebook. This is probably the biggest selling product of any line, and the one that the casual gamer is most likely to buy even if he doesn't pursue the remander of the product line.
Phase II -- the creation of sourcebooks and adventures. Since Conan is set in a pre-determined world, there would be a pre-determined number of nation sourcebooks and only a certain degree of latitude to create new ones. Probably there is a heavy purchase for the first few, but diminishing sales as the line grows larger and larger.
Phase III -- addition of anything else to the setting. I would think that this is where we are now, and most of the "big sales" products have already been created a while ago. At this point we probably get a few adventures and modules, but there are few canon nations left to read about and a large part of the world has been developed to a decent degree. The campaign line sort of fizzles out even if the present gamers continue their campaigns at full speed.
So, in a sense Conan is "dying" because there isn't a lot more that needs to be developed.
