There is a principle in storytelling: "Villains are the heroes of their own story."
Villains are never evil simply for the sake of being evil.
In their eyes, the villains see themselves as the good guys.
They have a reason for doing what they're doing.
Even if it is greed or the desire for power, villains feel justified in pursuing wealth and power because "that's how the world works". And, according to their own value system, they're doing the right thing and looking to win.
This is true of storytelling, but it's also true of life. Politicians who institute evil laws don't think of themselves as the bad guys. They consider themselves the good guys.
I find this to be a disturbing fact.
Evil doesn't feel evil, and so it's hard to tell when we are doing the wrong thing.
Most human atrocities were committed those who were doing the wrong thing. In hindsight they are able to see the error of their ways. But while committing their atrocities they felt justified in doing so.
They were afraid. They perceived others as a threat. They cared for their country and their loved ones.
Having good intentions or wanting to be a good person doesn't protect you from supporting evil or committing evil, because evil doesn't feel wrong, bad, or evil.
It's important for all of us to regularly revise our beliefs, values, and actions. Try seeing them from other points of view. We should all be questioning our assumptions and never assume we're the good guys. Otherwise our blindspot will lead us to doing and supporting evil deeds.