The Soviets somehow managed to combine cameras of great solidity with appalling manufacturing tolerances. My uncle once brought back some rangefinders from a trip behind the wall. He was hoping to sell them on for a profit, as they were so cheap to buy. Knowing I was a photographer, he asked me what I thought. Brand new out of the box, they felt as though someone had filled them with sand and loosened every screw they could find at the same time. Rough doesn't begin to describe them. Domestic consumption cameras were even worse than export models.
Lenses were often of exemplary design if they were put together properly. I imagine the workers were 'under-motivated' to put it kindly.