None of the Russophiles on this board will touch that question. General Sergei Surovikin, November 9th, 2022: "Having comprehensively assessed the current situation, it is proposed to take up defence along the left (eastern) bank of the Dnipro River," said Surovikin, standing at a lectern and indicating troop positions on a map whose details were greyed-out for the TV audience.
"I understand that this is a very difficult decision, but at the same time we will preserve the most important thing - the lives of our servicemen and, in general, the combat effectiveness of the group of troops, which it is futile to keep on the right bank in a limited area."
Since you don't understand anything about the military, military strategy or military tactics, it would never occur to you that the Ukrainians might blow up a dam to cut off the Russian forces on the right bank [west bank] of the Dniepr River.
But military people on the Russian side DID think about that. So they shortened their lines, and removed their men and the Russian civilians from danger.
And what do you know: The Ukrainians blew up the dam.
And the Ukies are STILL being turned into burger by the 8 to 1 artillery advantage of the Russian forces - including the press-ganged Ukie schlubs on the right bank in Kherson proper. 
"I understand that this is a very difficult decision, but at the same time we will preserve the most important thing - the lives of our servicemen and, in general, the combat effectiveness of the group of troops, which it is futile to keep on the right bank in a limited area." Reminder, the Russian were pushed into a 'limited area' on the right bank because their attacks at Nikolaev stalled and they were forced backwards, retreating day after day, until they were pinned against the river and left to acknowledge "IT IS FUTILE" to stay in Kherson.
To repeat, the Russians were pushed back from Nikolaev and recognized trying to keep Kherson was FUTILE. By their own admission!
fu·tile
/ˈfyo͞odl/
adjective
incapable of producing any useful result; pointless.
An apt description of Putin's Special Military Olympiad.
Why did they get pushed back from Nikolaev? That happened even before their air defenses failed to protect the Kherson bridge from missile attacks. You're gonna need a better excuse than 'we were afraid they'd blow the dam', especially since the history in that region clearly shows it's the retreating forces that blow the dam, to try and secure their flanks. The Russians refused international observers be posted at the dam as Ukraine requested, and then when Ukraine's counter offensive starts the dam mysteriously blows up. Russophiles, apparently ignorant that both the Soviets and the Germans blew this dam during their retreats in WW2 actually believe this is the work of the attacking side. Reason does not penetrate them.