Ken Schwaber quotes:

I estimate that 75% of those organizations using Scrum will not succeed in getting the benefits that they hope for from it.

Scrum is like your mother-in-law, it points out ALL your faults.

A manager's most important work is helping the people doing the work. Give them a goal and let them work. Remove any impediments that get in their way. Do anything that make them more effective or productive. Then the organization can capitalize on the fruits of their work.