Communism success has always influenced by the honesty and integrity of its protagonists .. If the so called vanguards of Marxism - Leninism apply the doctrines of karl marx and angels in letter and spirit then it can transform the lives of the proletariats. Its main goals , a classless society. Examples of which doesn't exist in the contemporary world , is not a utopian dream, economically its affects are also unparalleled.
The economic ideas in communism can be beneficial. Communism, when implemented in the proper manner, gives worth to every human being in the economic system. If the people in a communist system can maintain a sense of, "good for all," then the system can function and work properly without harm to the economy.
First let's get the important distinctions out of the way: communism is the end result of socialism-- a classless, moneyless, and society based on worker ownership of production/distribution and equality. Communism is theorized to be the step after socialism-- in other words, a perfected socialism.
Of course communism is economically beneficial when viewing it this way. There are no capitalists sucking wealth out of the working class or owning vast swaths of natural resources, the working class would receive all of the benefits of society's collective labor, and many socio-economic problems would disappear with the equal sharing of resources, etc.
Now, to the modern uneducated person's definition of "communism" meaning Stalinist state capitalism. State capitalism can be beneficial depending on who is running the show. Stalin was able to rapidly industrialize the Soviet Union-- creating a highly industrialized society from a very poor and still-war-torn state (ww1) and the Soviet Union was the fastest state to recover from ww2. Though this rapid industrialization and the side effects all came at the behest of the original goals of communism. The problem with state capitalism is that you inevitably will get people in power who do not understand socialist economics, they do not care for Marxism, they are reformers and these people destroy any advantages of the state capitalist system. Gorbachev and even Khrushchev are great examples-- but the Soviets still had many counter revolutionaries in the party.