Child molesters

Why are there so many child molesters being let out of jail and just required to register as sex offenders?...why are they even GIVEN a second chance? I have a little 4 year old boy and it BAFFLES me the amount of registered sex offenders/child molesters in my zip code (100+) i feel like the consequences should be LIFE. No ifs, buts, or ors....PERIOD. Nasty ass sick people in this world breathing the same air as us & our children ...