Capitalism exploits the greedy humans into generating wealth by rewarding them greatly, it also generates many jobs and assets for the economy. Yes that one person gets rewarded greatly, but many masses would not benefit if they never existed or were never motivated to do those things.
The lazy humans will fleece the system until there's nothing left. Some people need survival to motivate them to climb.
Socialism fails when you run out of other people's money. There's many examples of that.