Because they are sick. Sick in the heart & mind. Most people could never begin to understand how a mind like that works, the thoughts that go through their heads,so, they are just sick. It's sad for them, it's sad for the children, it's sad for their families. The people that commit these crimes tend to think that what they are doing is normal or that they are saving the child from something.
umm if u were old enough you would understand but since u asked it i dont suggest u are, but ill post it for those that are mature enough (age 13+) if not this age do not read, but they do it to rape them since they are not usually strong enough to run away, and killing people can just for be for multiple reasons theres like hundreds of reasons
I Honestly don't know why killers or kidnappers do what they do. Killers are just evil,and put their hatred on someone else physically,(many other reasons) and kidnappers are just sick people.(most of the time)
Honestly you can never really find out. But be careful first of all they are criminals they have sick twisted minds. There must be something not going right in there head. They might of had a bad life and is doing that just to get attention. I really don't no why they would want to do that but.... Yea