The factors that hindered the invasion of Russia by Germany was a low amount of German troops since Hitler was already fighting the US and Britain on one front he didn't have enough troops on the western side. The cold winter was also another reason, no one has been successful in invading Russia, especially in the winter months in which Russia troops are used to. Also the fact that Germany had little to no food didn't help. The Russian's were in their own homeland and could get food and supplies pretty easily but Germany on the other hand had to drive supplies to the front and their trucks often broke down and failed getting there.
