What causes shower/tub diverter valve stems to go bad ?

Just replaced the push button valve stem on my kohler shower/tub diverter and all is good - no more sticking valve.

My memory MUST be playing tricks on me, cause I swear this may the 2nd time I've done this due to sticking valve....


FWIW, it's a Kohler rite temp

They are mechanical devices which wear due to use. Sometimes they fail because they are used frequently, and other times because they are NOT used.

Go figure but it must have been to non use...
Thanks for the feedback. Always informative and I learn from it...