I've worked in the industry and I've heard that. They are "good" for several applications, maybe 3, 10, 100, something like that. But if you are servicing a several-million-dollar aircraft, it's easier to just replace them every time they are removed than to keep track of how many times they've been off and on.
Most commercial applications are not as critical. For people like us, you don't really have to worry about it. The vast majority of fasteners in your car are held in place only by friction due to prevailing torque.
(I've worked both aerospace and automotive.)
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I stop for people / whose right of way I honor / but not for no one.
Originally Posted by
bragi 
"However, it's never a good idea to overgeneralize."