My best mental model for the leadership of Russia's Ukraine invasion is an abusive parent who can't get his kid to bend to his will. Repeated failed attempts cause the parent to become more emotional, destructive, and out of control of himself, so we've gone from just an unprovoked invasion with airport attacks, attacks on radar sites, and occupation of the exclusion zone; to trying to assassinate Zelenskyy and starting to target refugees, residential areas, and shooting at nuclear plants.

As Ukranians continue to fight back and the West plays economic games instead of taking decisive military action, the escalation will continue until, by the end, everyone will agree that we should have just risked the initial nuclear threats of Russia rather than having Putin start launching nuclear weapons after having also leveled most of Ukraine and done whatever other increments of catastrophic forms of abuse come to his team's minds unyil then.

Alternatively, Putin wins before he feels backed that far into a corner, or maybe he's deposed before we reach nuclear weapons. But I really can't picture him backing down from confrontation, given that he was of a mindset to invade Ukraine.