Vintage mechanical cameras will run okay forever (shutter accuracy maybe a little iffy)

No failures on my clock (if you don't count my $10 Nikon N2000, which occasionally does not fire when the shutter is pressed), but my dad was a camera collector

2 brand new in box Rolleiflex SL35Es, dead on arrival
1 jammed Rolleiflex SL 35 (shame because the lenses are so nice)
1 abused Pentax 67II where the electro magnets wouldn't hold the shutter open, resulting in it not cocking
a bunch of Graflex XL and Linhof Super Rollex backs that never spaced correctly
Linhof Press 70s that never synced properly (mechanism did not wind and cock correctly)

As a former camera repair tech, he tried, but none of these have successfully been revived