Exists in e.g. Germany for serious crimes under the name of preventive detention, which basically means that you stay under lock, but not prison conditions, even after your sentence. Consider it an asylum for the not criminally insane, that is, people who can understand guilt. Starts at about armed robbery, especially when recidivous. Even possible for youth offenders though exceedingly rare.
For less serious cases: Just because our justice system isn’t retributive doesn’t mean that deterrence isn’t a part of the equation, you don’t want to acquiesce Ocean’s 11-style “I did it because my wife left me and it’s not like she’s going to do that again” get out of jail free cards. Generally the threat of prison over here is a “screw your head on straight yourself or we’ll do it for you” kind of situation, e.g. it’s not optional to get used to holding a regular job when you’re in German prison, they’re deliberately building that routine and make sure you’ll have a skillset to get a job with.
Also life sentences always have the possibility of parole. Not offering people that possibility is actually against the European Convention on Human Rights, as it infringes on the free development of personality: By taking away the possibility of release, no matter how far off that may be, you right-out prevent people from bettering themselves. Minimum time until parole is 15 years, average hovers somewhere around 20 years. And yes you can get life and preventive detention, the evaluation criteria differ.