Juveniles do make mistakes because they are not thinking properly at that age.
However some Juveniles may do things that they really meant to do and can be dangerous to society if set free early.
Some Juveniles do deserve to serve a life prison sentence for things such as murder because some Juveniles have murdered and robbed people in cold blood without any regret and those Juveniles do need to serve a life sentence.
However some Juveniles who do something serious do have regrets on what they did as a Juvenile and can be rehabilitated and would be safe in society again.
So I think that some Juveniles should serve life sentences in prison while others should be given a second chance if they can prove to the court and society that they are no longer a threat.