Yeah, that is a vicious cycle that feeds on itself. There are other reasons as well. With a short time based release cycle and updates that often include new features users get the latest stuff quickly and don't have to run Rawhide.
Fedora has multiple branches in parallel (Fedora 13 - Fedora 10 now for instance not counting EPEL 4 and EPEL 5) that you can't really keep track of all of the changes easily from a developer perspective.