When any form of resources belong to "everybody", then technically, these same resources belong to no one.
An interesting observation had been posted on Arfcom several weeks ago in their megathread about the Chernobyl series on HBO. I can't dig it up at the moment but basically, one poster wrote about how his engineering professor or someone in a similar academic position had been one of the American advisors sent to the USSR shortly after the Chernobyl power plant went kaboom and he had observed one of the reasons why famine had been so prevalent in Brezhnev era Russia.
When all resources belong to everybody, they belong to nobody. And since they belonged to nobody, nobody gave a fuck anymore. This guy had been present at one of the grain harvests and he watched how grain being loaded into lorries would be spilled everywhere and none of the workers even paid attention until an entire carpet of grain blanketed the ground and the facility where the lorries were loaded on trains. All of the spilled grain were simply left there to rot or be gobbled up by circling birds and other wildlife. The trucks that transported the grain from the railheads, had also been in states of disrepair and abhorrent conditions because nobody had bothered to inspect or repair them. When some of the trucks broke down, they were left there. And when other vehicles, loaded improperly or overloaded, toppled over, they were simply left on the roadsides and their drivers would just walk away. Thus, entire harvests were wasted and only a few percent of the harvested grain made their way to processing facilities.
That is one of the most serious unintended consequences of communal labor and communal resources. Since nothing belongs to anyone, no one takes pride in their work anymore. Why bother, since they are not going to be enjoying the fruits of their labor anyway? That is also the reason why factories and manufacturing plants in Communist countries lack almost all forms of quality control. The workers simply will not give a fuck since they are getting paid the same meager wages and sustenance. Even if the top brass implemented quality control efforts, the supervisors underneath them realize that they are being treated no better so why should they bother putting in extra work for nothing?
The bottom line is simple: If you do not give people a reason to be proud of something that they earned or invested in, they will simply not give a fuck anymore. And this is how the very fabric of society will collapse in a communal society.