Good excerpts from Ries and Trout's The 22 Immutable Laws of Marketing:
The target is not the market. That is, the apparent target of your marketing is not the same as the people who will actually buy your product.These excerpts come from "The Law of Sacrifice" chapter. Typically, your best marketing strategy is to focus on a narrow segment of the market. Ironically, if you select the segment carefully, you may end up having a much broader appeal than if you try to be all things to everyone.
The target of Marlboro advertising is the cowboy, but the market is everybody. Do you know how many cowboys are left in America? Very few. (They've all been smoking Marlboros.)