I can understand this mentality... but I don't agree with it still.
I have had friends die. Shot or stabbed to death over petty shit in Oakland. I never wanted anyone to suffer, or be killed for it. I did want them to go on to live a happy and full life, if they could be rehabilitated. There are undeniably bad people in the world who will never be safe to be in society again, but I fully stand behind Norway's system as well: there's always hope. Maximum sentence of 20 years of rehabilitation, if they aren't, they be in for another 20 years, and always have it re-evaluated.
Prisoners should be treated with respect and care and should try to become educated, learn their errors, make amends, and become better people. How does our prison system cultivate this though? Isolate people except for minor contact with other prisoners who will bond due to how terribly they're treated by the system. Minimal attempts to truly help them recover. The point is entirely punishment and revenge, and it doesn't make things better. It doesn't make anybody or any part of society better. I don't think there's ever been any evidence that punishment ever does anything effective. And it shouldn't be viewed as our primary objective when facing crime. Attacking the roots of crime, the circumstances, the conditions of the people are wildly more effective (and since somebody is thinking it, yes, more cost effective too) than what we're currently doing.