Russia still struggling in Ukraine

 ISW:

Russian forces face mounting difficulties replacing combat losses in Ukraine, including the possible death of the commander of the 150th Motor Rifle Division near Mariupol. Russian efforts to deploy forces from Armenia, its proxy states in Georgia, and reserve units in the Eastern Military District will not provide Russian forces around Kyiv with the combat power necessary to complete the encirclement of the city in the near term. Russian forces made limited, unsuccessful attacks northwest of Kyiv and did not conduct offensive operations in northeastern Ukraine, toward Kharkiv, or toward Mykolayiv. Russian forces did make limited territorial gains in Donetsk Oblast and around Mariupol and continued to target civilian infrastructure in the city. Russian forces will likely continue to reduce the Mariupol pocket in the coming days, but Russian forces likely remain unable to conduct simultaneous attacks along multiple axes of advance.

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Russia is increasingly pulling forces from its international bases and redeploying damaged units that were rotated out early in the invasion of Ukraine to replace mounting casualties. The Ukrainian General Staff reported that Russian forces are deploying additional Eastern Military District (EMD) reserves to Ukraine as of March 16.[1] The Ukrainian General Staff additionally reported that Russian command “refused” to deploy elements of the 5th Combined Arms Army (CAA) to the Kyiv advance “due to heavy losses in the south.”[2] It is unclear if the Ukrainian General Staff means Ukraine intercepted a request by Russian commanders around Kyiv for reinforcements from the 5th CAA that was denied, or if they are only assessing that Russian casualties in the south are draining reinforcements initially intended for Kyiv. Social media users observed elements of Russia’s 58th Combined Arms Army based in Russia‘s proxy republic in Georgia, South Ossetia, redeploying in likely transit to Ukraine on March 15.[3] Russia has already pulled forces from its base in Armenia and will likely soon redeploy forces from its base in Tajikistan. The Ukrainian General Staff additionally reported that Russia is forming additional battalion tactical groups (BTGs) by consolidating units that suffered losses in the first 10 days of the Russian invasion and graduating cadets from military higher education early to replace officer losses.[4] Russian forces will likely face further difficulties integrating these units into its command and logistics structures.

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The attempt to consolidate forces into operational units is further evidence of the significant casualties suffered in the operation.  The Russians are still unable to take strategic objectives because the forces they do have are too spread out to be effective in overwhelming the Ukrainian defenses.  They appear to be trying to do too much with too few troops and significant equipment losses.  They are also seeing open opposition to their war effort within Russia leading Putin to complain about "traitors."  I suspect they are having moral problems with the troops they do have at this point.  

The Russians also do not appear to have adequate forces to occupy the space they are trying to control.  This will become a bigger problem as they attempt to control urban cities.

See, also:

Ukraine claims ‘serious blow’ to Russia with ‘liquidation’ of another top general