Do the cups of headsets with cartridge bearings wear out? On my bike I have an FSA headset Orbit X-CX which has cartridge bearrings. I re-grease the headset a few times each year and have recently replaced the lower bearing after ca 13,000 miles.  The upper bearing still feels smooth.

On a loose ball style headset if badly adjusted or after excessive use the cups would wear.  With a cartridge bearing the bearings run on the cartridge itself which is replaced.  Does this therefore mean that the cups should last the life of the bike?
The bearing races themselves get replaced, but what can happen is the races becoming loose in the frame. I can't imagine that happening just through wear, though, you'd have to pull and replace the bearing races hundreds of times. Normally that is the result of either a crash deforming the races, or the bearing not being quite square when someone hammers it into the frame. To avoid the latter use a proper bearing press or fake it with a length of threaded rod. In general, any time you find yourself wanting to use a hammer on a bike you're doing something wrong.