A frame can experience plastic deformation (aka internal/external cracks) if you string it well above the recommended tension range for too long.
Aside from that, they will not "wear out" unless from abuse/hitting the ground/leaving in your car on a summer day/etc.
I still use the POG I used in high school. I string it at the top of its 75lbs tension range, and it's still like buttah. I also have a few other decade-plus-old frames that still play like the day they were new.