One of the main Marx's points is that the added value is created only by exploitation of the working class by the capitalist.
In USSR all production is owned by the people (state), therefore there's no need for added value and exploitation, the workers earn enough to sustain their life.
You have to sustain living of all citizens, regardless of their output, therefore they should all earn enough.
As a result, engineers earn pretty much the same as janitors and professors and government officials - the money they earn is not connected with the value they produced, so you have a major economic disbalance, and you can't use money people earn as purchasing power typical for market economy.
As a result, you can't balance that on the level of individual business entity, you have to balance it on a state level. The only way you can do it is by splitting retail and production monetary policies.
This way, everyone earns the same money, and the obvious imbalance is fixed by limited access to retail goods not necessary for survival which you can't purchase if you didn't "deserve" it. This requires a complicated system of retail goods distribution (it was managed by Gossnab [
en.wikipedia.org] ).
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What happened with the fall of Soviet Union (the so called shock therapy) - was uniting the retail and production monetary systems. Production were forced to account costs with money they earn from retail in the same manner as market economy works. Instantly there was lack of money, all production switched to barter, economy collapsed and we had to rebuild it from scratch.
Edited 1 time(s). Last edit at 10/12/2017 11:49PM by Kstatida.