Right!, you are absolutely clued in on CURRENT Russian military strategy.
what a joker, as in Bidementia
They're still taking a lot of casualties. Eventually, the Russian army had enough in WWI. So far, they're not breaking. But the war goes on long enough, maybe they will decide that they had enough.
The Ukrainians hate the Russians. So they're motivated to fight.
What is the motivation of a typical Russian conscript? They're using fear to intimidate him to fight. But at some point, that may not work anymore.
This is a war of attrition. It's all about who's going to break first.