Hi I'm a student and was told to research Operation Barbarossa for my WWII class and reasons that it failed. For the most part, I found out what i wanted to know, but in most every source that i have looked at says that the Nazis were unprepared for the Russian winter, and no other real concrete reasons other than that reason. Also i would like to know more about the other plans that preceded Operation Barbarossa. Thanks in advance.
hi! you may find something of interest in these previous posts
Is there any point during Operation Barbarossa that Axis victory over the USSR was obtainable?
Why didn't Army Group Centre take Moscow during Barbarossa?
What was the biggest contributing factor to the failure of Operation Barbarossa?
Looking here should set you off to a good start.
Here are some examples:
The German High Command grossly underestimated the mobilization potential of the Red Army.
The Red Army proved it could replace huge losses quickly, and was not destroyed as a coherent force.
The German army could not be supplied sufficiently for prolonged combat; indeed, there was not enough fuel for the whole army to reach its objectives.
Soviet railroads could at first not be fully used due to a difference in track gauges
I would suggest searching the subreddit for some recommended books on the Eastern Front / Operation Barbarossa, and then looking into these points in more detail.