Some people can be born with effectively broken brains.
Take any trait, generosity, comedic ability, levels of empathy, etc. All of these traits can be modulated by DNA (and epigenetics of course). It only makes sense that out of the millions of babies born, some baby will come with little ability to experience empathy. That baby could grow up to take pleasure in sick things, to grow into a sadist.
To be clear, by broken brains I’m not referring to learning disabilities or people who disagree with me etc. I’m referring to brains that cannot function in society due to an accident of birth – brains that have effectively chosen a life strategy incompatible with with the stable society the rest of our brains have chosen.
Also to be clear, those people with broken brains?.. They are mostly in positions of power.