Has communism been successful?
It is very difficult to argue that communism has been successful in any country where it has so far been tried.
Communism has not made any country prosperous and stable. The Soviet Union never had enough material goods to keep its people happy. Neither does Cuba. China has become wealthier only after rejecting communism in everything but name.
Communism has not made people equal in the way it was supposed to. Communist governments and societies have always had elites who had much more in the way of material goods than the common people. We see this, for example, in North Korea where millions starve and the elites live well.
Communism, then, has not brought equality to its people and it has not brought prosperity to economies that have embraced it. It has not been successful.