larry johnson provides evidence and theory about the russians at the start of the ukie war;

Western military analysts frequently deride and ridicule the Russian military for its slow-pace of advance in taking back territory from Ukraine in 2023 and 2024. But the perceived slow-advance was not the result of poor leadership or bad tactics… It was a manpower issue. On the eve of Russia’s full-scale invasion of Ukraine (which began on February 24, 2022), the Russian Armed Forces significantly outnumbered those of Ukraine in terms of active personnel. But even that number is misleading. If you are going to capture defensive positions held by Ukraine, you need ground forces.

Russia entered the Special Military Operation (SMO) in February 2022 with an estimated 280,000 ground forces, while Ukraine fielded an estimated 130,000. However, only 125,000 Russian troops entered Ukraine at the start of the SMO. Under traditional doctrine, an attacking force should have four times the number of troops in order to have a reasonable chance of defeating an entrenched army. The fact that Russia deployed troops that were a fraction of what was required to conquer Ukraine is prima facie evidence that Putin was not intent on occupying all of Ukraine.

Let me put this in perspective using the Battle of Stalingrad as a benchmark… The Battle of Stalingrad was a turning point in World War II, involving massive Soviet forces across multiple fronts and phases. The term “Soviet ground force” refers to Red Army troops (infantry, armor, artillery, etc.), excluding air and naval elements unless integrated into ground operations. During the initial defense (August–November 1942), the Soviets field ~187,000–200,000 soldiers on the Stalingrad Front under Yeryomenko. The Soviets suffered heavy casualties during those four months and the heavily depleted Soviet units were reinforced by ~50,000 replacements monthly. The Soviets broke the back of the German 6th Army between December 1942 and February 1943 with an additional 1,100,000 soldiers that attacked the German flanks as part of Operation Uranus (November 19–23, 1942), which resulted in the encirclement of the German army.............more...........