You don't want me to open debate on the fact that the Germans beat themselves by invading Russia then ?
Bang on there News. The only person that stopped Hitler was Hitler. The list of his mistakes is long and notable (this isn't exhaustive, just what I can think of in a couple of minutes and I'll just skip over invading Russia since it's already mentioned):
- The postponement (and eventual cancellation) of operation Sealion until the Luftwaffe achieved air superiority when the British were on their knees
- the change of focus from bombing British airfields to bombing cities
- his refusal to take the most direct route to Moscow because that was the route that Napolean had taken - resulted in the failure to take Moscow before winter '41 (especially after the invasion began at least a month late)
- His shift in focus in '42 from taking Moscow to heading East for Stalingrad
- His obsession with Stalingrad because it bore his enemies name. It had no real strategic value
- Letting Mussolini suck him into sending troops to Nth Africa
- His steadfast belief that the Allied landings would come at the Pas de Calais so even a week after D-Day refused to send reinforcements to Normandy
- and the big one for me that really spelled the end: after the Japs bombed Pearl Harbour, despite the fact that they were supposed to invade Russia from the East, he declared war on America which brought them into the war in Europe