[adczxqep] Communism will end poorly

Who made the earliest correct prediction of how communism, when practically implemented, would turn out?  Was the prediction early enough as to be interesting, or pretty much after the fact?  Was it a wild guess, or what was the methodology of making the prediction? What was wrong with other methodologies which made the wrong prediction?

Inspired by Ayn Rand, though she was a reaction rather than a prediction.