While this was a useful design criteria (make it dead-simple and dependable) it also led to a great deal of over-engineering of many components to provide the level of durability required. The question that is left unasked here is "why?" A part that is twice as large as it needs to be will be dependable and you can create masterfully simplistic designs with them, but it will have more limited capabilities for a given weight/mass. The reasons were two-fold: Soviet manufacturing was not up to the task of delivering consistent quality near the bleeding edge of materials science, and Soviet troops were mostly conscripts who would horribly abuse equipment through poor training and lack of education.

From WWII through the late 70s this strategy served the USSR quite well, but by the 80s their "cheap and simple" approach was leaving them further and further behind. At the low-end of the performance and design spectrum this left them with some very nice tools, but the high-end was owned by the west and in the early to mid 80s an inflection point seems to have been passed where high-end units could completely dominate a particular battlefield.