Management vs. Leadership

I was listening to The Critical Path podcast last week while at the gym and had a thought.
(at 22:00) Horace Dediu says the following,
“The dilemma is that management and leadership are one of these water and oil types of things. It turns out that distinction between management and leadership: – Management is keeping things running. Leadership is breaking things and not keeping things running the way they are. 
Leadership is about change, management is about the avoidance of change. Many times we embody with the word manager both of these things. so there’s an almost implicit recognition of the duality of management.”
I keep hearing folks talking about how frustrated they are when dealing with management in relationship to the work they do. Some managers get the bigger picture, others are totally heads down and don’t want to be bothered.
Are we expecting too much out of managers? People whose job is to keep the status quo vs. leaders – those whose job is to disrupt that work?
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I sent the above to a few co-workers I admire. One of them had the following to say,

“My adage on organizational hierarchies:

If you aren’t thinking past the work of “management” then you shouldn’t be promoted past the level of “manager.”

Have I over-simplified sufficiently? “
Spot on.