Maybe in the absence of human greed.

Because greed corrupts any system including communism.

Capitalism works because of greed and the concentration of power to a small group of people. But the more successful it is, the more inequality there is and eventually the system will fail … for the majority not the minority.

Communism failed because of greed and the concentration of power to a small group of people. The more they concentrated power the more inequality there was and eventually the system failed.

The problem to any human system are humans … conversely, the solution to and human system are humans.

We are our greatest ally and we are also our own worst enemy.