Why do bad guys always succeed in real society?

The villain's way of doing things is unconventional, less constrained by morality and conscience, pursuing practicality and utility, understanding human weaknesses, being good at trying to figure out the minds of superiors and leaders, taking advantage of loopholes in rules, pretending and playing any role.

From a social point of view, I quote a passage from Jin Yong's This Guy Wei Xiaobao to answer you:

As far as Wei Xiaobao is concerned, most of his actions are not commendable. But in a society like the early Qing Dynasty, such a move was very beneficial to him. In a different environment, modern countries such as Switzerland, Finland, Sweden and Norway have very strict laws and very strong social sanctions. The result of opportunism is usually very bad, and doing good things is far more beneficial than doing bad things. People like Wei Xiaobao who immigrated to the past, I believe that in order to adapt to the environment, they will choose a well-behaved life. Although, it is hard to imagine that Wei Xiaobao will behave. In a certain society, if the result of corruption, cheating, cheating and breaking the law is more favorable than living a clean and honest life, then it is this society and system that should be reformed. If such a story is described in the novel, it is mainly the society and the system that are condemned. It's like novels like Officialdom in the Sky.