"Most Soviet camera designs were perfectly sound – it was more often that the construction itself was lacking. TOE engineers learned on the assembly line, then went back to the UK and stripped and reassembled every single camera that came into the UK."
I grew up in Poland and my dad said the exact same thing - that when he was young, if you managed to somehow buy yourself a brand new Soviet motocrycle, fresh from the factory, the very first thing you did was disassemble the whole thing to bits, lubricate, and reassemble everything at correct torques and in correct places. Then you could go and safely use it.
[0]https://kosmofoto.com/2018/12/zenit-e-russian-camera-review/