Communism never “worked” because Communism always had to live under pressure, (the USSR), from WW2 to the Cold War the USSR only had a few years to thrive… and somehow the USSR got the 2nd best economy amidst all of this! Yugoslavia tells a different tale, but it fell along with all of the other major communist countries in the 90s as Ultranationalists saw the communism as a threat after the USSR collapsed and the Warsaw Pact fell apart.