“Experience has taught me that advertisers get the best results when they pay their agency a flat fee. . . . It is unrealistic to expect your agency to be impartial when its vested interest lies wholly in the direction of increasing your commissionable advertising.” 

– David Ogilvy, Confessions of an Advertising Man, 1971, New York: Ballantine Books, p. 71.

“Make sure that your agency makes a profit. Your account competes with all the other accounts in your agency. If it is unprofitable, it is unlikely that the management of the agency will assign their best men to work on it. And sooner or later they will cast about for a profitable account to replace yours.” 

– David Ogilvy, Confessions of an Advertising Man, 1971, New York: Ballantine Books, p. 71.