Greetings, appreciated @meno.

In my opinion it is the uncontrolled avarice of man that has always led to the failure of projects that in one way or another could be beneficial for society and individuals. If we talk about socialism or capitalism, in both cases we find factors that negatively affect the principles that underlie the bases of these ideologies or economic models.
We can also analyze the results that history has left us. In general, socialism, communism and other leftist tendencies have only left misery and impairment of human rights in the world.

But I insist, regardless of the model adopted, it has always been the alienating nature of the human being that has caused these models to fail.

All best, Piotr.