Why's that? The end goal of the revolution is surely international communism, because otherwise there will be destabilizing elements (capitalists) remaining, but in the context of our historical reality where revolutions occurred in relatively poor agrarian societies which had their stolen wealth re-used by capitalists against them in the form of arms races, embargoes, sanctions, terrorism inside their borders, opposition candidates, propaganda, etc it's understandable that the modern communist countries aren't the most ideal exemplars of international revolution. And that's fine, it's not like they're committing anywhere near as much violence as capitalist countries are and have.