Karma. I hear a lot people these days saying how the psychopaths who ruin everyones lives deserve punishment and are due karma due to their actions.
But aren't they already suffering by existing here without sympathy? Can you imagine living without sympathy? Their lives already are miserable with them being stuck in the lower emotional states of fear, anger, pain and hunger. physical gratification is about the limit of their experience, the best they can hope for in their life.
Their current existence is state of hell. Survival, that is all.