Did an exchange with the Spetnaz years ago that involved spending time in the USA and Russia with combined military operations. At the time, we were looking to work on counter terrorism things with them as partners but it was also an exercise in understanding the tactics of a major military.

What is happening in Ukraine right now shows me that there has been very little evolution in their tactics and mentality. Years ago, they were a product of heavily reliance of gaining and maintaining fire superiority over an adversary with large weapons as well as quick movement to penetrate gaps. Not saying that this is necessarily wrong as you always want to gain fire superiority while maintain the ability to move fast....but with the Russians, they
(1) Are typically conscripts (even more so now as many of their better soldiers are fighting for The Wagner Group ...a PMC)
(2) They do not have a strong NCO corps
(3) They are highly centralized in their decision making
(4) Their weaponry is not very accurate causing them to place a heavier reliance on massed fire thus expending mass quantities of ammo and creating collateral damage situations.

Why is this an issue in Ukraine? Because the Ukrainians (the birthplace of one of my great grandfathers) have been very hard for the Russians to "place" in particular situation. They are adaptive, highly unpredictable, and are fighting on their own "homefield" in an urban/city environment with a lot of variables. This is causing huge issues with the Russian boots on the ground as they really do not have the experience or knowledge to react quickly. They are not as quick to recognize ambushes, they are poorly led on the ground, they cannot use their major strength (armor) as easily in an urban center (I love that the Ukrainians are hunting them with hunter/killer groups armed with Javelins and NLaws). Both weapon systems that we have given them (Javelines and Stingers) are so much better than the Russian equivalents and in this setting, they have a tremendous ability to inflict max damage to an invading force that is poorly led on the ground and does not operate in a system where an individual can make a quick decision and others will follow).