Russia struggles to get troops and equipment into stalled Ukraine operation

 ISW:

...

The Ukrainian General Staff reports that the Russian military is continuing efforts to replace personnel and equipment losses but struggling to do so. The General Staff claimed on March 25 that Russia has established a base in Russia’s Bryansk Oblast to repair and rehabilitate equipment pulled from strategic reserves.[2] The General Staff asserted that much of Russia’s reserve equipment is unusable or in very poor states of repair, with essential gear—including engines—stripped out of many vehicles. The General Staff added on March 26 that the Russians are attempting to refurbish old T-72 tanks as part of this effort.[3] The General Staff also claimed that the Russian military is lowering its standards for conscripts and recruits and has been forced to use a higher proportion of conscripts in combat as it has suffered losses among its professional soldiers.[4] We have no independent confirmation of these reports, but they are consistent with observed patterns of Russian operations and losses in Ukraine and with ISW’s earlier assessment of the state of the Russian personnel reserve system.[5]

Morale problems within the Russian military are becoming more serious and apparent. Reports that the soldiers of a Russian unit killed their brigade commander by running him over with a tank and, more recently, that the commander of the 13th Guards Tank Regiment of the 4th Guards Tank Division (1st Guards Tank Army) committed suicide likely indicate a general breakdown of morale even among first tier Russian combat units.[6]

The Russians continue to try to concentrate forces for renewed fighting around Kyiv, however. The Ukrainian General Staff reported on March 26 that additional Russian forces from the Eastern Military District were being sent into Ukraine at an unspecified location.[7] Eastern Military District forces have been engaged exclusively in the Kyiv and Chernihiv region.
...

There is much more.

I suspect the Russian equipment problem is two-fold.  Some of it is shoddy construction and some of it is the result of poor storage operations that allow some of the parts to deteriorate which can make the equipment useless.  There is also probably poor field maintenance during an operation.  The Russian equipment is also clearly vulnerable to the western weapon systems that Ukraine has been provided.

The Ukraine counterattacks appear to be well thought out and the Ukraine forces are not making the mistake the Russians have made of overreach.  Russia continues to have a force to space problem created by its initial rapid advance before an area is secured.  This has also exposed a supply problem for the Russians.  The counterattacks expose the Russian force to space problem and their inability to control the terrain they are on.

See, also:

Report: What Russians Did to Their Commander Shows How Much Trouble They're In