He's not really known for being a bad leader, to be fair. Kind of the opposite. A bad leader wouldn't have been able to rally an entire country to commit genocide.
Yes he is. His military decision making was thankfully shit, his hatred of Jews caused a brain drain ahead of the war; nuclear research wasn’t prioritized because it was considered a “Jewish science”. Also his rearmament of Germany was completely unsustainable and would have collapsed the German economy if not for the onset of the war. Effective demagoguery =/= successful leadership.
If I set out to make a thousand year empire that only lasted 11 years would you consider that successful leadership?
He was great at leading them to lose. I am only defining leadership in the sense of "leading people." He was great at that. Just not at tactics or strategy or sane ideas.
Okay, so to be clear, your critera for "great" leadership doesn't include any sort of decision-making skills nor effective delegation when said leader is out of their depth?
If I worked at a company that had leaders making a long series of bad calls at a tactical and/or strategic level, for instance, I shouldn't call that "bad leadership"?