Here are a few interesting links that relate to why managers and leaders fail:
This post from Leadership Now discusses why many managers and leaders fail after taking on a new job. Hint: Relationships are key.
Second comes this interesting little story passed on by Johnnie Moore. Hint: People notice - GREAT or BAD - what leaders do.
From Dave Pollard's blog (via T&D) comes this great post called, Will That Be Coordination, Cooperation, or Collaboration? Although this does not relate directly to how managers and leaders fail, I think that many confuse these terms (with each other and also with direction and participation). Poor managers often give lip service to these terms instead of creating genuine involvement and engagement.

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