We get punished and shunned when we don't display the same kind of emotions that others do, and the explanations we receive appear to be meaningless and unfounded to us.
To say something like:
"How would you feel if someone hit you? That's why you should not hit other kids!"
...makes no sense to a psychopathic child, but we quickly learn that we have better pretend to understand or else...! This is how we learn that nothing is what it seems and that pretense pays.
How do you propose that a child can understand that this is not how everybody do things when we get praise if we do it well and are punished if we don't?
Add to this that we soon find out that we can use other people's emotions against them, we can often control them and make them do what we want, and we can get what we want by using tactics that others would feel bad about and therefore do not use, because we ourselves feel fine when we do it. All this to us proves that we must be stronger than everybody else, so how come everybody else keep saying we are wrong and that all those who seem to suffer so easily and are so easily controlled are better than us? To a child this doesn't make sense!
But it might make sense if our caretakers understood that there really are different kinds of emotions in different kinds of people and that not everybody have the same ability to feel empathy - or remorse, for that matter (I understand why empathy is a useful emotion to encompass, but I'll probably never understand what is useful about remorse). Not having the ability to feel empathy has nothing to do with being evil, it is a neuro-psychological predisposition that the child - or the adult - has no saying in. We are born that way, and we cannot choose to learn how empathy feels.
Let's for the sake of getting my idea across say that psychopaths are like computers and normal peeople are like dogs. Psychopaths can not choose to learn how empathy and loyalty feels anymore than even the most sophisticated computer can learn to understand poetry from an emotional perspective. It doesn't mean computers aren't useful, they're useful but in different ways than f.x. dogs who have deep instinct for loyalty and will generally be willing to die for their 'tribe'. Normal people didn't choose to be born with an instinct for loyalty and cannot choose to not feel it anymore than a dog can choose to not have empathy for their group or have loyalty for their group's alpha dog. But abuse a dog or try to program for the wrong operating system, or download a file with a trojan horse to your computer, and both the dog and the computer will become dysfunctional.
There are programs so rare hardly anybody know they exist, but are they evil because they aren't compatible with Windows?