you feel he doesn't deserve to be saved

This seems very wrong to me.
To say to somebody "you're no longer worth living" is god-like and not suitable (and so I decline the penalty of death).
I suggest that we can feed a hope: that even a murderer can change his mind and can work at his/her character and can try to get a healer. This hope we should feed - so I want to suggest - especially if we don't know (and that's the normal case) which evil was done before to the later criminal. I don't want to suggest that all criminals should be hugged but that they should treated as fair as possible.

More than once I asked myself: would I - if occasion would have been given to me - have been able to killing Adolf H.? Not in persuasion of his cruel crimes but in preventing them before done. Would I? If someone gave me a ticket to ride into - let's say - 1920?