In my opinion, it happens because of a couple of things; firstly, our society now provides numerous excuses for peoples' behaviour (economics, had a tough life, not really the person's fault, etc. etc.) they really didn't mean it and saying that magic word "I'm sorry" which they think forgives all actions, and, secondly, society should be about rehabilitation rather than punishment.
As far as I am concerned, the primary duty should be punishment not rehabilitation or forgiveness. People make choices in life and everyone is responsible for their actions. People talk about revenge being a bad thing but I don't think it is. After all, Justice is Revenge dressed in a nice suit.
Criminals usually get bed and breakfast and the victim gets life, either physically, emotionally or mentally or a combination of the three.