|Credit: The Black Rhino|
First, business does not require us to make the change. Second, I'm just plain tired of keeping up. Third, the world of Open Source Software always looks so much more appealing (not to mention my growing fascination for Hackintosh computers).
Call it a mid-life crisis. I'm in an industry (photo retouching) which has lost over 50% of it's workforce here in the United States. The way we work at Photo Grafix has changed a lot in order to stay competitive. I've even started a new venture called Black Rhino Illustration, which focuses on cartoon illustrations to feed my creative soul and build up some much needed extra revenue!
So, it's just not worth it anymore to upgrade all the time. Also, as a teacher, I focus on fundamental skills that transcend Photoshop, it's sundry versions and leave all the fancy stuff to other folks.
My workflow is not dependent on the features of CS6 or CS5 (which I currently use). If my skills are not good enough to keep up or I there are incompatibilities with my Macintosh system software, then maybe I'll consider upgrading.