The other comments here do not mention the most important part: the fiscal recession cycles caused by publicly traded, unregulated markets. In other words, the predictable 8-year pattern of booms and busts - the creation of a speculative bubble of growth followed by that bubble popping - that defines modern Capitalist economies.
No recession or depression in recent memory has truly been caused by a mismatch of supply and demand. Instead, they are caused by our complex financial investment apparatus; they have nothing to do with the “producing and buying things” side of Capitalism and everything to do with the “Moving money around” side of it. A thing - real estate, tech startups, comic books, whatever - begins to grow in value not because it is actually worth more but because people are speculating on its future value.
This is why Uber keeps growing in valuation despite never making a profit: the people buying Uber stock are not betting on Uber making a profit, but that other people will buy Uber stock in the future, further increasing the price of the shares. This is a bubble that will eventually burst, when they run out of potential investors to keep propping up the share price - but you maximize return on investment if you jump ship at the very last moment.
The '08 housing crisis is a great example. It followed an almost identical speculative bubble, except with mortgage-backed securities.
While these things will happen to some extent in Socialist countries with market economies, there are two reasons why they hit Capitalist countries extremely hard.
The first is that modern Capitalism has made every person into their own little Capitalist. Retirement funds are tied to the stock market, rent and housing prices aren’t fixed. Ephemeral financial-sector bullshit affects ordinary people when it has no reason to.
The second is that strong regulation can prevent the worst effects on ordinary people. Socialist governments can fix prices and forgive debts in order to minimize the effects of a fiscal downturn.