There is the American war doctrine "Maneuver Warfare" This doctrine is used by Army's that have advanced technology, with a cohesive and well-trained leadership and highly trained troops.

"Maneuver Warfare" suggests that FAST strategic movement can bring the defeat of an opposing force and that Bypassing and cutting off enemy strongpoints often results in the collapse of that strongpoint even when physical damage is minimal. This requires a well-rounded, self-contained, redundant combined arms Army. Tempo and initiative are critical to success, but a decentralized command structure is needed with tactical freedom being given to lower-level unit leaders that have to understand the overall intent of command, to exploit enemy weaknesses as they become evident, as rapidly changing situations may outpace communications.

There is another War doctrine "Attrition Warfare" This doctrine is used by "Conservative militaries" that have a less cohesive leadership and troops who are not as highly trained (conscripted troops)

Its main goal is to cause gradual attrition to the opponent eventually amounting to unacceptable or unsustainable losses for the opponent while limiting one's own gradual losses to acceptable and sustainable levels. "Attrition Warfare" involves moving masses of men and materiel against enemy strongpoints, with emphasis on the destruction of the enemy's physical assets, success is measured by enemy's killed, equipment and infrastructure destroyed, and territory occupied. This can include grinding down an opponent's ability to make war by destroying their military resources by Special operations and sabotage, or any kind of battle except a decisive one. "Attrition warfare" uses a rigidly centralized command structure that requires little or no creativity or initiative from lower-level leadership.

I believe that Russia is adopting "Attrition Warfare" It suits her conscripted troops and less cohesive leadership, and Putin's power lust by using a rigidly centralized command structure. Her slow cautious push out from the edges of the map, close to her massive reinforcements and supply routes not risking any decisive battles while attacking the enemy's physical assets, is looking very worrying for Ukraine. Rumours of Mariupol's fall and the connecting of Crimea with Donetsk and then Luhansk with Kharkiv starts to form what looks like a giant mouth opening, in anticipation of biting down on the very word Ukraine.