“A consultant is a person who is supposed to know more about a subject under consideration than his client. Once an engineer has acquired a reputation for superior knowledge and discovers that there is a demand for his services, his future career depends on what he expects to get out of life. If he longs for financial success and social prestige, he will find that his aims can hardly be satisfied without creating an organization. Once the organization exists he becomes a slave to it. His income increases, but so do his worries. Sometimes he has sleepless nights because he does not know how to handle all the orders rained into his lap, and at other times, because his overhead charges exceed his income. In any event, the Tax Collector sees to it that his income does not assume staggering proportions. He may still believe he is a consultant, but in reality he has turned into a business man and executive, equipped with all the prerequisites for stomach ulcers.
On the other hand, if he derives his principal satisfaction from practicing the art of engineering, he will desist from establishing an organization and concentrate all his efforts on broadening his knowledge in the field of his choice. In order to be successful in this pursuit he must be not only willing but eager to spend at least half of his time on unprofitable occupations such as research or the digest of his observational data. Therefore, his money making capacity remains unlimited, but in exchange he has fewer worries and retains his freedom of action. This is the type of occupation which has turned out to agree with my disposition.”
(Karl Terzaghi, 1958)