More musings from me. Musings only, because I really don't know for sure. I think there probably are some people who develop "mean streaks" very early on. For example, a child who starts to torture and kill insects, and seems to enjoy it. This might be in spite of the fact that no mistreatment of the person is evident. I think, unless calm and intelligent interventions are made with such people early, that small beginnings may develop into large end results, ones that we really do not want to see happen. It is no favor either to society or to the person themselves to let that happen. It requires intelligent attention to a person's development to manage that sort of thing.