Russia have lost nearly 400,000 people so far. They've crippled their economy and industry, not to mention scuppered any progress they made since the 90s. Ruined their growth in international standing and currently bending over for China and getting reamed on tech for the war by Iran. They have lost countless flagship military installments and their hold over the black sea.
In the nearly 10 years since their initial invasion they have captured no more than 20% of Ukraine most of which was captured in 2014s Crimean annexation.