Weather is vital in any military operation. If the Germans had a perfectly favorable weather for them they would be in a much better position (i.e.: when attacking, always have summer like weather, when defending, always have terrible muddy weather). They were able to win battles losing 5 times more men than the Germans. I think that this characterizes numerical superiority, and kind of a massive one. The soviet union had impressive capabilities to replace lost soldiers. Any other power could not suffer 8 million casualties in 1 year and still maintain the strategic initiative after. Well, that myth has some foundations: The operational performance of the Red Army was nothing very good, however, they won the largest war ever, so their strategic leadership must have been quite decent. That is simply wrong. Strategic offensives are nearly always envelopment operations. - Lend lease was critical for Soviet victory. Without it collapse might have ensured. I agree partially with that. Even if it was small, Lend-Lease was important in a front were warfare had a very close outcome. Germany had very good operational and tactical leadership. But had bad grand strategic performance. Why? Well, i think that the fact the while in the operational levels there were military genius running the show while in the grand strategic level they had a corporal in charge can explain those events. They were very hard men. However, with the rest of this sentence I disagree. strategic offensives are nearly always envelopment operations :that is theoretical,in the best circumstances ,but given the status of the two opposing armies in the east and the absence of decent roads,it was rarely searched and even more rarely attainted .About the corporal in charge,sorry,but this is only a repetition of post-war myths:the stupid Hitler without whom Germany would have won the war .