Even Marx himself predicted that a necessary period of transition from Capitalism to Communism would be the "Dictatorship of the Proletariat". We can all debate the niceties of Marxism, but the fact was that its formulator and primary theorist believed that the people would need to be "shepherded" to the Utopian Marxist society.
The real problem for Communism is that the industrialized countries never bit. There were a few abortive revolutions in the mid-19th century, but the leadership of these countries were smart enough to recognize that political liberalization was the antidote to a restive working class. Most countries saw enfranchisement of larger numbers of people, increasing influence of legislative assemblies, and a more populist approach to government.
That's why the only countries that actually grasped on to Communism were primarily agrarian states like Russia, China and Cuba. In pure Marxist theory, agrarian states have not developed to the point where they are ready for the Communist revolution. That's why you have offshoots like Marxist-Leninism, Maoism, Trotskyism, Stalinism and the like, all offshoots required to explain why economies dominated by agrarian workers should skip the whole mercantilism/capitalism stage and go straight to Communism.
My personal feeling is that Communism, like other Utopian socio-political and economic ideologies like the various strains of Anarchism and Libertarianism, are impossible to implement. Anyone attempting to will have to make so many compromises that the ideology itself becomes compromised.
That's not to say Marxism doesn't have its uses. Certainly Marx's insistence on history being seen through the lens of economics was critical to the transition of that entire branch of academia from political narratives to a more comprehensive view of the functioning and interactions of historical societies and events. But as a socio-economic and political model, it's a flop. It can't be implemented without dictatorship, and as we've seen so many times, once the dictators gain the power to effect the Communist transformation, they are so corrupted by that power that they actively kill the revolution themselves.