I think that might be related to whether someone sees people as good and bad, or as being capable of doing good and bad things.
From how I see it, classifying people as just good and bad is very reductive in that you assume that bad people do bad things with bad intentions and the opposite for good people. That means that if you’re certain that you’re a good person, you don’t need to question your own actions or motives because you can’t do bad.
If you however see people as capable of making good or bad actions with good or bad intentions, you should realize that people you see as good can do bad things and vice versa. That means you should always examine your own motivations and your own decisions to make sure you’re doing the right things for the right reasons.
I personally believe this is why it is so common among certain activist groups to harbor some absolutely atrocious beliefs that seem contrary to what they’re working for.