Why do men become communists? And more particularly, why do they become communists despite everything that we know about communism? In the last century, as many as 120 million people were murdered by Marxist-inspired regimes. And yet, certainly in the United States and in Western Europe, we have the remarkable spectacle of virtually an entire intellectual class that has been seduced by the allure of Marx’s ideas… It’s not Marx’s labour theory of value [or] dialectical materialism that has drawn people to his philosophy, and it’s certainly not the interminably boring Das Kapital.

Dr Bradley Thompson asks, “Why Marxism?”  

Thompson refers to Marx’s “angry, spitting moralism” as a chief enticement and in this longer video he elaborates on its idiocies, referring to the result as “a philosophy of malevolence.” It seems to me one can’t explain the appeal of Marxism without addressing the psychological license that it offers, specifically for coercion and petty malice. It’s a golden ticket for a certain kind of sadist. Why Marxism? Start with rationalised envy and a vindictive desire for power over others, wrap it in a drag of altruism, and then take it from there.

See also this.