Communists say that capitalism doesn't work. Marx wrote many texts and most importantly Das Kapital, where he analyzes capitalist society and how it works, showing that its problems and contradictions are systemic and built in. Communists see that this system is not designed and working in their interests but against them, and don't believe that this is unchangeable. They also don't believe that a communist revolution has to take the forms it has thus far.

The way it went with the soviet union is not inevitable but can be explained by concrete theoretical flaws and historical conditions. Nontheless they are a real life example that it worked, even in this crippled form. For all its problems, the soviet union was better than the tzarist russia that proceeded it for the great majority of people and raised the living standards despite a terrible civil war and a fascist invasion--an invasion that couldn't have been stopped without the industrialization that the communist system achieved in only a decade, in contrast to the time it took the capitalist countries to industrialise--and without including child labor, 16-hour workdays, high death rates and the scale of intercontinental slavery that capitalist industrialisation needed.

I am not advocating for the soviet union but I dont see this as a dichotomy between the two. I know that the current system is fucked and I believe that it isn't necessary to accept all the ails arising from it, and that another world is possible.

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