Ran across this quote from Mary Schmidt, a marketing consultant, today. I thought it was great:
"I already knew that."
I sometimes hear this when asked for free advice. I'm tempted to reply, "Well, great! Then why aren't you doing it?" A good consultant can help you test assumptions, focus on key activities and help get "it" done, whatever "it" is -- launching a new product, reorganizing HR, and so on.
Also reminds me of the theme of one of my current reads-in-progress: Strategy and the Fat Smoker: Doing What's Obvious But Not Easy by David Maister.