Because no one gives a f about some ethnic Asian Russians dying. Are they even 'really' Russians? To average Russian probably not really. When Slav people from Moscow and Leningrad start dying in high numbers vs like a couple so far then people will start to care. Mass mobilization will put an end to all the facades.
This ......
Because since 1914 th war heavily depends from ammunition, weapons and coordination....
Advantage in manporver doesn't matter so much...
Equipment, weapons, intelligence and survilance matters everything....
For example the same disappointment with Tzar was after huge losses due to lack of good coordination....despite Russia had not lesser machine guns, really usable airplanes and cannons...
With lack of well coordinted artillery supoort Tzar's generals in 1915-1917 turned for example Baltic countries area into....idiotic meat grinder for lads . from locals till guys from siberia...
Mountain of machine guns and Isle of Death were damn notable areas....
Hate vs monarchy had born....when they provided delayed artillery support and xxxx casualities in 1 day then was ....nothing special...
And even officers knew that they have not worse artillery than germans...in not lower numbers and with then not that bad ammo supplies...
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Since Russia's main advantage vs Ukr was...
More than 10X advantage in MRLS launchers and long range guns number + ofc without any doubts also in air defense and infamous Thocka missiles....
The same Uragan MRLS...70... vs 72 in Belarus and ~900 MRLS....etc...
These are numbers reported by these countries in 2017 th...
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Fundamental part of russias Kremlin propaganda is to claim technological advantage and superority in these suprweapons number and ammo they have...
Mobilisation will ruin this image quickly......
Also for financial reasons: f.m will allow plebs to delay monthly debts payments to banks and loan shark firms....

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Next stuff: they does have land, mortgage in different locations etc...and money and kids they want to see rich, healthy and lucky....and these too does have $ and mortgage and businesses...not only in Russia...
They also not rare cases does have cancerofobia....
Also if they will use tactical nuke .....this will with 0 doubt prove for plebs in Russia that Russia is technically 3 rd world country.....while claimed that are 1 st world country and well skilled in high tech to beat plebs in Ukr with conventional war...
They most likely also had underestimated a lot of factors in EU...
Like trolling Prince of Pain....living in info bubble and claiming that others are living in info bubble...
Term " cheap natural gas " doesn't exist in EU 15 years in row...
It was correct term until 2007 th...