Why is Evil so Attractive?

This question intrigues me because I think there is a different attraction for each person: money, power, etc. I think it would be interesting to explore/contrast someone who kills someone for money versus someone who kills a person for the sake of enjoyment. Is the motivation for these two different scenarios essentially the same? Where does evil come from? If it is inside of us, what awakens it? Is evil the "easy way out"? What are the temptations in our lives? Is revenge necessarily bad in all contexts? There is definitely something alluring about being "bad", rebelling, and disobeying rules for me and I often wonder if it is because I have been forced to be "good" my whole life.