Capitalism is the best and most efficient form of production and distribution in the world. However, there can be greedy capitalists. That is why we have the SEC and other regulations. If it is over regulated it becomes stagnent. If it becomes too greedy, workers are hurt. It has to be tweeked, not done away with. It isn't evil in and of itself, but only the people involved.
Communism doesn't work because it treats everyone the same (idealy), but this creates lazy workers because if one works hard, he gets the same as the lazy one. If one invents, he doesn't get the benefit of it. Soviet Russia is the prime example.
Socialism doesn't work. It allows some restricted capitalism, but has so many government benefits, rules, regulations, capitalism becomes stagnent. OR, it becomes like Nazi Germany, socialism with one party rule.
Unrestricted capitalism worked well in America in the 1800s, but did create a lot of poverty and squaller in England due to their limited space. In America, if one didn't think he was paid enough, he could just up and leave and head west, stake out a claim for land and farm or ranch. American capitalism unrestricted capitalism was tempered by a strong Christian influence. Henry Ford had trouble with his workers fighting, quiting, not being productive. He asked his pastor what was wrong. His pastor said if you pay the man a decent wage so he can provide for his family you will get good productive workers. He went from $1-#2 a day to $5 a day. Unheard of at that time. His productivity skyrocketed. Model T's came down in price. More people could buy them.
When America outlawed prayer and Bible reading in schools in the 1960's, the hippy movement, far left influence, Great Society, etc. America lost its way. We have become more socialist, made stupid "free trade agreements", and created a permanent dependent underclass.