When I was a child and saw those heart breaking true story - made for tv movies on Sunday nights, some of which were about kidnappings and murders I thought kidnappers and/or killers were just insanely cruel humans by nature - there was no purpose or reason for their crimes I thought. They just simply 'did'. As I got older I realized many times it is sometimes weird people, especially you men, with mental problems.

It is humans who refuse to get help or do not realize there is help for sick thoughts in the head. Example # 1 is the couple in California who adopts or brings in the young girl who was heading nowhere in her life, but trying to get back on her feet. They threw her off a cliff and she died. It seemed like the perfect crime for the woman, until her past caught up to her. She killed a few people before and set a few of her homes on fire prior. Wouldn't this woman realize that her evil ways would eventually get the best of her? Naturally these cowards move from one region of the USA into another to start over.

1. Are people like her confident or truly gullible? I think they get a big head and are very gullible. Then that is why they get caught. I mean these sick people just keep killing for more and more money. isn't $200,000 enough for them after a couple killings? Why the need for more money?

What I am trying to say is that if a killer killed a few people and got a total of $300,000 well that can give them money to completely pay off on a small house and buy a brand new car, new clothes, new tv, etc. But when these serial killers move and move and kill and kill it is simply stupid. a normal person would not kill, but a 'normal' person also knows when to stop. these people do not know when to stop.

I think some sort of mental illness is responsible for their ability to rationalize their actions.

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....or just lack of any shred of a conscience (borderline or actual sociopaths)....

IMO, there are some people (types mentioned above, criminals in general) where there's nothing you can do (short of a breakthrough in science ie a brain transplant) with them to stop them from doing whatever immoral things they want to do at any point in time in their life. The same thing goes for trying to make them a better person. They don't bring any redeeming qualities to the world, especially after they get to a certain age (typically adolescent years on forward): they just take up space.

I know it's from a movie but The Dark Knight summed it up best

"Because some men aren't looking for anything logical, like money. They can't be bought, bullied, reasoned, or negotiated with. Some men just want to watch the world burn."