I saw this documentary on the History Channel that pretty much attributed Germany’s defeat on the Eastern front in WWII to Russia’s climate. As the Germans were about to take over Moscow in 1941, winter caught them almost by surprise. They then realized their troops were not equipped to fight or neutralize an attack amidst such a terrible cold. German soldiers who survived depicted horryfying scenes. Most of their comrades were dead-frozen in the position they fought. The documentary made particular emphasis on the might of the German army in comparison to the Russian, which was rather weak by all standards. Stalin even forced the prisoners deported to Siberia to put on a uniform and fight at all costs or else they’d be shot.
Is there an expert on the topic who can offer more information? What are the other theories as to why Germany lost WWII?