What is your opinion about Communism?

[Anomalocaris]

A good idea in theory is a good idea in theory.

Your example about drunk driving is terrible. That's obviously a bad idea in theory and in practice.

I don't need to give any examples of a good idea in theory because I know what "in theory" means, Jesus.

In theory, if everyone contributes to the common good, society advances.
In practice, you need to get everyone on board with this idea and that just doesn't happen. When you see your beautiful plan not working because the people are uneducated or simply disagree, you force them to comply... And thus a dictatorship begins with the obvious crappy results.

This happens in any society.

If people can see directly relationship between dire consequence and not contributing to the common good, common good can be attained remarkably effectively against severe adversity.

The thing that helped to cripple soviet style communism is ironically the fact that it was even less able to effectively establish a convincing relationship between dire consequence and not contributing to the common good in day to day life, than in many capitalist societies. So pervasive inefficiency, laziness, shirking expanded into ever larger parts of the Soviet economy.