Gary Ridgway (the Green River Killer) just stopped. He reached middle age, and lot interest in it. I guess if there is a certain amount of hormone drive in sexual murder, that could happen.
I read a fascinating article a long time ago by a clinical psychiatrist who took some time out from his practice to research what made some abused children become abusers, and some not. He looked into the backgrounds of a large number of men incarcerated for very violent crimes, and discovered that almost to a man, they had been violently abused by a parent. But when he researched further, he found out that they hadn’t just been beaten bloody or had broken bones: they all very specifically had gotten head injuries from their abusers. Then he discovered that of the few men who had not been abused, nearly all had also had a head injury as a child-- they’d been in car accidents, or fallen from significant heights, or something.
Meanwhile, his group of abused children who had not grown up to be violent themselves had suffered great abuse-- he had people in the sample who had had limb bones broken-- but had, nearly to a person, never had a head injury.
So, it looks like if you want to raise a serial killer, start out with not making your kid wear a bike helmet, and then, put them in PeeWee football.
I wish I could find this article to cite it, but I read it in a print journal something like 18 years ago, and I have not been able to track it down.
As far as them being men and white, there are probably some things that contribute to that: the head injury may not make you violent per se, as much as it impairs judgment as impulse control (albeit, I remember reading someplace else that Aileen Wuornos, and a UK female serial killer who started out as a teen, had had head injuries). Women who lack impulse control may face other problems, or they might be violent with their children, but may not fetishize violence so that they become serial killers.
Whites also get a pass a lot where black people don’t. So maybe there are black people who commit serial-type crimes, but they are pursued more aggressively, or just watched more closely in the first place, so they get caught before they rack up a body count. Or maybe it’s economics. Every serial killer in the 20th & 21st century has seemed to own a vehicle, and had at least some disposable income. Black people have fewer resources on average. Actually, one of the reasons I suspect the police got the right man in the Atlanta child murders, was that he was middle class, and owned a car.