Secrets of Consulting

I'm reading a book titled The Secrets of Consulting, by Gerald M Weinberg. Gerald talks about what it takes to become a successful consultant in today's business world. Here is what I have learned so far:

• If they don't ask for your advice, don't give it. Consulting is the art of influencing people at their request. Gerald says that among consultants, the most prevalent occupational disease is offering unsolicited "help." It is bad for your bankbook, and not only does it not work, it usually backfires.
• If they ask for your advice, give it... for a price. Never fail to tell them how much it will cost, or you will not be taken seriously.
• There is always a problem. And it is always a human-related problem. Even the most technical problems can be traced back to human error or oversight.
• Do not call what you offer a "solution." A solution can only exist within the context of a problem. You don't want to suggest they have problems, because problems imply mistakes or shortcomings on the client's part, and nobody likes admitting to that. Instead, call it an "improvement." Nobody will have a problem with it if you suggest that they can improve the way they do something. It doesn't offend their ego.
• Never promise more than ten percent improvement. If it goes above that, it qualifies as a "solution," and thus a problem. This doesn't mean you cannot go above ten percent. You can, as long as you make sure they don't notice it.

Gerald believes that the intriguing phenomena where consultants who do outstanding work almost never get invited back, whereas those who seem to be accomplishing nothing get contract after contract, can be explained by the above rules (or secrets, as he calls them).

I think calling them secrets is rather apt, because they are, at first glance, irrational. After all, Gerald says, an inexperienced consultant's first impulse is to sit down and start fixing the client's problems and do an outstanding job at it to emerge as the savior of the day. But when you think about human nature, especially in the business world - where competitiveness and pettiness are the norm - the only thing a consultant's heroism accomplishes is a "thank you very much for your work, please do not come back."