oh i got a good one for preventive maintenance..... old otis ucl 1960ish, the wires from the controller to the generator insulation got so old and brittle that it broke off and ground out on the inside of the splice box. emails went flying.....customer wanted to know why we don't check this on our visits? after getting my ear chewed off for about 10 min. about how i didn't catch this i "nicely" ask the customer why his expert elevator consultant didn't check this??? no answer, and more emails went flying!!!!