Socialism will work when each and every human being in the society, each and every one, considers the best interests of all others in the society to be more important than his own best interests. It has zero chance to succeed until then.
Actually there are many examples where such indoctrination has worked in the short term, i.e., one to two generations; but by the third generation, the populace notices that some are consistently more equal than others. In addition to the Soviet Union, There are examples in various 19th century American communities where ownership was in common.
Nope. It won't work even then. See Economic Calculation in the Socialist Commonwealth by Ludwig von Mises
The inevitable failure of a socialist economy has nothing to do with people's intentions or willingness to cooperate with each other. Socialist economies fail because they do not allow for market prices. Without market prices it is impossible to know if any sector of the economy is making progress or just consuming capital.