They’re disgusting, aren’t they?
And any talk of a negotiated peace settlement really makes them mad. They get even nastier than they usually are.
Any negotiated peace that results in a net gain for Russia is unacceptable. If you reward any behavior, you are very likely to get more of it.
The goal is for this war to be such a strategic disaster for Russia that not just Russia, but any other potential aggressor country decides that it just isn't worth the risk.
You may not agree with that approach, but the motive is to reduce the number of wars that get started in the first place.