Training Risky has a point.
When working for Andersens (now Accenture) the description of a consultant was: somebody who borrowed your watch to tell you the time.
I did reckon that often having an outsider to take a good look at what you were doing was no bad thing and questioning the WHY was a healthy exercise. In addition: WHERE, WHEN and HOW were also healthy questions for a business to ask and often better that it's done by somebody outside the firm. That said there were some eye watering sums of money spent on 'rebranding'. The amusing but sad reality was that the Firm's own internal processes left IMHO something to be desired.
O-D