Takes care of recidivism, though. But I wouldn’t advocate it for that reason.
Someone who will commit murder at the age of 15 is very badly damaged, and will need a great deal of help to not be a danger to others in the future. That’s the compassionate route.
Almost zero governments will want to spend the money. Sadly, it’s cheaper to keep them locked up.
I find interesting that there’s a lot of “might”, “maybe” and “possible” when talking about rehabilitation, but not as much attention is paid to the “absolute” of another person’s death. Possibilities and potentials won’t bring that victim back to life.