Though Ukraine has taken very heavy casualties too, they have been in general mobilization from the start, growing their forces and replacing their losses. Russia, for political reasons, not so much. They went in with 150 to 200K contract soldiers. Western estimates to date show 70 to 80K casualties. That's around HALF of the original invasion force chewed up, not counting the slow trickle in of new contract troops, Wagner Group mercs., etc., and the trickle out of deserters and refusenicks. It's so bad that the Ukrainians are now capturing Russian sailors and strategic missile troops in infantry units and manning tanks. An unmitigated shit show. 
So....since contract soldier moral wasn't bad enough, lets throw in conscripts, convicts (authority problems, anyone?) and recent "shanghaies", poorly trained and poorly armed since they're running out of modern kit and the professional trainers are dead, wounded or fighting on the front themselves. They can do the conscript thing now since the lines are mostly within or bordering on recently acquired "Russian territory."
This debacle will be studied at length for generations on how to NOT fight a war....um...special operation. The biggest shit show since the Italians got their asses kicked in Greece in 1941.
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