Born to be Bad?

These are my angels who, on occassion, put on their devil horns. However, they are really very good kids.

As I caught a glimpse of the news this evening I heard that there was yet another school shooting. This is so sad and it made me think about that kids and adults that do these horrific crimes. My question, as broad is it may sound, is how do "good" kids turn into "bad" kids/adults?

I believe that every human is born to be "good", so what makes some turn out to be "bad apples" (sorry- I have eaten a lot of apples lately)?

In my daily ventures at work I run into some pretty shady individuals, and since I do not believe in conspiracy theories, how did these people turn out so "bad"? Were they "the kids not left behind?"- no punn intended Georgie. Or is it much more simple, in that low expectations were placed on them by the people around them or perhaps they were bullied. I do believe that good people can and do fall into difficult circumstances, but why are some able to rise above and others take the road that should not be traveled...I do not believe there is a simple answer. Perhaps one day there will be an understanding and answers.