I think a major problem Putin has is a classic one that befalls many autocrats in their final years - his own ego and paranoia. Like all autocrats, Putin is a control freak and he trusts no one (nor should he). Like all megalomaniacs, he craves the credit for any victory. He expected a quick win so he could flex for the RT and Sputnik cameras as a military mastermind, a savior of ethnic Russians, and a conquerer of their evil Ukrainian oppressors. He badly underestimated Zelenskyy and his ability to rally the citizens of Ukraine to mount an impressive guerilla defense of their homeland.
Putin has studied the whole history of the various chess moves that ultimately filled the vacuum of power left by Stalin with Khrushchev; moves which began even before the ol' butcher took his last breath. Putin knows that at this point the oligarchs would likely skin him alive in Red Square tomorrow if a majority of them would unite on who his successor should be. So he deliberately keeps them all divided, only partially informed, pointing fingers at the military brass and each other. That way they all look like fools, and no clear commander who could potentially lead a movement to depose Putin emerges. It also makes for awful war strategy, as Hitler found out when he employed it for the last 18 months or so of WW2 while he was high as a kite on various drugs.
