Posts: 266
Threads: 32
Joined: Jan 1970
I have a 15C in the exact same condition.
My opinion has always been that this is simply as a result of taking the machine in and out of its case. Even if you otherwise treat the calculator with the utmost respect, that friction from the case eventually exacts its toll.
I have a number of other Voyagers which show logo paint wear -- the paint is partially rubbed off for some distance from the edge of the logo. That's the forensic evidence which leads me to my opinion.
Posts: 331
Threads: 47
Joined: Oct 2005
I think that when the paint is badly worn some owners then rub it all off deliberately (my mother did this to her gas cooker markings!).