That is Marx's theory in a nutshell. We're supposed to believe that everyone would just jump out of bed every morning eager to contribute their little light to the collective beacon.
And maybe they would. If their little light was equipment manager for the Swedish Bikini Team. But I doubt there are many people who salivate at the thought of garbage collection or unclogging toilets. So who does THOSE jobs?
Well, it's simple. The kommisars determine what jobs need to be done -- for the good of the collective, of course -- and who is best suited to do them. And before you can say "Leon Trotsky," you're snaking out a floor drain for a crummy two-room flat and a drunken proctologist who takes too great a delight in his work.
Liberals FEEL that basic human nature can and should be "changed" for the better good.
Conservatives KNOW that human nature can NEVER be changed, and that we must deal with that fact.