The Russians obviously understand that territory is, in a lot of cases, a liability.  High cost in taking it, and ongoing cost in holding it in many situations.  The only time area really matters a lot is at the end of the conflict.

This is a pretty easy concept and I don't think that the reason it seems to escape the 'Ukrainians' is because it is difficult.  It's one of  the main supports for my hypothesis that the 'leadership' of Ukraine considers the loss of Ukrainian souls in this operation to be 'a feature, not a bug.'

Ukraine is focused on 2D (aka, area.)  Russia is focused on 3D (aka, volume as in 'gas in the tank'.)  Pokrovsk is a good illustration about how 'area' is very cheap and pretty much there for the taking when the enemy runs out of gas.  The goal is to get the enemy into a situation where they are completely out of gas and without options to get more so that they don't just run out of gas locally and as the result of an unforced error (Kursk <-> Pokrovsk).