Planned by the party, not the workers. Workers lacked any voice in the party, it was no different than any other authoritarian rule in that aspect.
I grew up in the USSR, nearby farms were controlled by a kolhoos which was headed by someone important in the party, the farmers had no say in what was to be produced or to who their produce goes to, only the party decided that. The same control existed for every other industry, party gave the orders with no input from a single worker, commonly even going against workers in their orders.
I would love a system where workers actually controlled the means of production but the USSR was not that.