Communism was based on idealistic principles that were not effective in practice.  Corruption and mismanagement amongst the top leadership ruined the concept of equal distribution in communism.  There was no stimulation or incentive provided for productive workers.  Due to oppressive government practices and shortage of food amongst masses, people rioted against the Soviet regime. 

Communism was based on idealistic principles that could not survive in practice for very long

Communism proved to be an idealistic rather than a sustainable system of government and management.  It relied on communist principles that we should all earn and possess the same amount of money regardless of knowledge, competencies, and skills we possess.  This did not prove to be a satisfactory solution in reality.  As human nature usually works, it was impossible to divide the society’s resources equally.   If leaders had not misused the communist system and if such a huge shortage of food had not been created, perhaps the communist system would have lasted somewhat longer.  Sooner or later communism would have collapsed because it went against basic principles of human nature and psychology as people like gathering possessions, comparing and competing with each other as a matter of power, status or prestige. 

Corruption and mismanagement ruined the concept of equal distribution in practice

Workers in Europe were taken advantage of and exploited through the dominating political party.  Communism and the type of economy it was based on propagated the idea that the production should be governed by the workers with the overall guidance from the state.  However, the way this worked in practice is that farmers were responsible to produce corn and to donate it to the government.  The government was then to provide farmers with approximately equal amounts of corn.  However, this whole process did not go smoothly as prescribed in books and imagined to work in practice.  The whole process was hampered with corruption and mismanagement and eventually came to an end.  

There was no stimulation or incentives provided for productive workers

Communist regime in the Soviet Union proved to be more a utopia than a working system as it produced too many poor people and then the rich bureaucracies.  In addition, the communist system in no way stimulated the production and the industrious workers, as there were no incentives provided to the hard-working employees.  People were yearning for an open and free market in which they can operate, earn a decent income and prove themselves.

Common people eventually rioted against oppressive government as they were lacking food

People were being imprisoned or executed if they said anything that was different from the ruling communist ideology.  As basic needs of people were not being met in the Soviet Union due to lack of food, civil unrest followed suit.   Country after country revolted against the oppressive Soviet regime that kept the countries enslaved to communist ideology and ruling.  Socialist countries went bankrupt in the end as there were no monies and food left for those who needed it most.