Hitler visited Napoleon’s tomb before invading the USSR... he was arrogant.
Hitler was stupid NOT to provide the German armies with the winter uniforms, etc.
Hitler foolishly thought that the Japanese would reciprocate by declaring war on Russia and opening a Siberian front — foolish considering the spanking that Zhukov had given the Japanese during their ground war against Russia years earlier.
Hitler was fooled by Canaris, who sabotaged negotiations with Spain, which could have led to the Germans overrunning Gibraltar.
If Hitler was a “genius”, his megalomania, paranoia, and overconfidence effectively negated any genius.
I am of the belief that the Axis forces could actually defeated the USSR (even though invading a country that huge with such a brutal climate is always a logistical nightmare) if the following three great mistakes were not made by Hitler:
1) Failure to capture Moscow early in the summer months when it was doable instead of diverting troops to the South in order to encircle Kiev, which could have waited IMHO.
2) Failure to provide winter equipment and clothing for the troops. Elementary in a country such as the USSR known for its harsh climate. If Hitler had studied Napoleon as carefully as he studied Frederick the Great, he would not have repeated Napoleon’s greatest mistake.
3) Failure to treat the indigenous populations well. After decades of oppression under Soviet Communist rule, the native peoples in the USSR generally treated the Axis Forces as liberators. By treating them as badly as Stalin did, this ridiculously misguided policy only succeeded in creating legions of partisan armies operating behind German lines, sabotaging the German war effort, and cutting off German supply routes.