FT.com says that
"The ground war in Ukraine, however, has exposed the limitations of Russia’s modernised military. As many as 15,000 troops have died in battle and 20 to 60 percent of its precision-guided missiles have failed, western officials have said. Ukraine claims it has killed 15 senior Russian commanders, including seven generals, an indictment of Moscow’s failure to build an effective officer corps."
“The Kremlin is scared of its own officers, so they try to run the war from the command centre on Skype,” Luzin said. “The generals can see what’s going on but they have to carry out the orders they get from there and lie to their command that everything’s not so bad. So they get unfulfillable orders, run to the front, direct every tank with their hands, and they get killed.”
I have also heard that the design, manufacture and reconditioning of tanks and heavy weapons is staffed with men around retirement age, because young engineers don't want to work there, and that a large proportion of the "reserve" stock is unservicable, having been stripped down for repair or cannibalised for parts. Since the war against Ukraine was planned by Putin's tiny inner circle, military planning and logistics were not involved and were taken by surprise, unprepared.
