We have all known people like the every day RH:
Arrogant, but not grandiose. Condescending, but not cruel. Seeks attention, but is not exploitive. Over all shallow, but capable of some degrees of relationship with a handful select people.
Though I have known others, a cousin comes to mind now:
"D" is over all shallow. Over decades, I have never known D to express even a minor concern or an interest in anything or anybody that could not immediately benefit himself- or later in life, his child.
D is a life long show off from childhood. D is arrogant and is madly in love the sound of his own voice. He is openly condescending of others that lack his income and perceived "value". D is overly demanding towards wait staff and contractors- and enjoys "summoning and dismissing" people.
Yet.... D has never killed anybody. Nor, has he ever even seriously harmed anybody. D does not commit crimes. No serious emotional abuse of the ex. She just got tired of D one day, wanted something different- and walked out.
In short.... why do some everyday low level jerks murder, and others never even commit minor crimes, let alone murder?