If importing a celebrity CEO is seldom a good idea, why would you want to use that hired gun called management consultant? He (or she) may know even less about your business and may have never even been a manager or business owner. How can they contribute anything?
Since I spend a lot of my time selling that service and playing that role I had better have a good answer to that question. Some of my thoughts on the subject are already documented in the article ""Consultants: How to choose, use and not abuse them." See: Ezine articles.
The consultant cannot know your business, your environment or your issues better than you. But he (or she) can add the value of their own knowledge, experience and skills to better analyse the problems or opportunities and develop solutions and action plans with you. The consultant should assist with brainstorming, open up new possibilities to consider, suggest some different strategies, tactics and techniques to get where you want to go. They should be practical and fit your business needs, budget, timetable, priorities, capabilities and corporate culture.
A good consultant should challenge and stimulate you to do better. You are not hiring a friend to remind you how smart you are or to tell you that you already have the right solution.
More than that? You will have to pay me. I am a consultant after all.