In Marketing Warfare, Al Ries and Jack Trout wrote:
To play the game well, you first have to learn the rules, or principles, of the game.and
The problem with marketing today is not just the lack of rules. The biggest problem of all is the failure to realize that one ought to have rules in the first place.Good marketing doesn't come just from understanding and applying sound principles of marketing. It doesn't even come just from understanding your market. Good marketing requires both market understanding and principles.
To rectify that problem, marketing people must start to systematically examine the history of marketing and formulate the strategic principles that govern the outcome of corporate battles. Nothing today is as important as strategy.