Sometimes we place a lot of expectations on one person that they tend to perform better because of that expectation and because of the time and effort we invest in them. This is something that happens a lot in classrooms: a teacher as a lot of expectations towards a student and invests a greater amount of time in helping her, so that this particular student ends performing better. This is called the Pygmalion effect or a self-fulfilling prophecy.
That tends to happen a lot in marketing as well. Marketers have expectations about a certain product and drive more of their efforts towards that particular product so that it performs better, not because it’s the better product or because the public felt in love with it.
Another form of self-fulfilling prophecy in marketing refers to consumers and their behavior. Marketers create expectations about the kind of consumers that will buy their products. Based on these expectations marketing and advertising campaigns are drawn so that they please and persuade the intended target. With no surprise, latter analysis will show that the expectations held when the campaign was planned were correct. However, it’s also likely that it was the campaign that made those expectations become reality.
If you target a specif audience with your campaing, it is probable that it is the members of that audience that will buy your product. There is nothing wrong with that, but by doing it you can be losing some costumers to whom the product migh be of interest. It’s one thing to study the market and see who buys your product and then target that audience. A totally different thing is to create a campaign based on assumptions. Usually it’s the latter case that prevails.