Russia needs to recruit some new soldiers, according to British intelligence, the Ukrainian army is killing so many Russian soldiers the Russian military has had to move soldiers off the front lines and pull them back to protect the supply convoys. The biggest reason Russia isn't advancing as fast as they thought. They also claim more soldiers are being pulled from other regions in Russia.
Also Putin is putting his own Intelligence agency in the doghouse as its been so wrong on the Ukraines ability to defend itself.
Putin has no way out of this now , they isn't good for a rational end to this conflict.