It simply is not. The idea of blaming military losses to the concept of ''General Winter'' is a way to hide the fact that an army you viewed as inferior (like the Germans viewed the Russians for example) came on top by superior tactics/strategy. The same idea was being spread by the French during the Napoleonic wars. They were already on the retreat when the winter kicked in and a huge fraction of their manpower was lost during the offensive outside of the winter months:

1835 Denis Davydov published a military-historical article, titled "Was it Frost Who Devastated the French Army in 1812?", where he demonstrated that the French suffered casualties in battles during relatively mild weather and listed actual reasons. He used not only his own observations as arguments, but foreign opinions as well, including French authors.[3]

The Leavenworth papers explain 3 case studies of fighting the Russians in winter and how the weather factored into those campaigns. Note that the winter froze the muddy roads after the Russian rain season which actually made the Germans advance quicker and both countries had to adapt to the weather. Russian weather reports from General Zhukov during the battle for Moscow also consistently report higher weather temperature than the German reports. http://usacac.army.mil/cac2/cgsc/carl/download/csipubs/chew.pdf

Admittedly, the Soviets did prove slightly more well-prepared - especially when it came to mobility in snow, from wider tank tracks to large masses of combat skiers - whereas the Wehrmacht had to struggle to bring in the winter gear after the campaign dragged on longer than expected.