Do you sometimes get the feeling that Internet portals, search pages, social networks, e-commerce, and other Web sites are not necessarily designed in order to maximise user convenience and benefits? We do, too.

Why – you might ask? For a fundamentally similar reason to why some retail stores place the most popular items (e.g., bread, milk) in the furthest possible place from the entrance; that shopping malls seem designed to make sure you get lost at every single visit; and that popular magazines drown the content they carry in a sea of advertising with no clear table of contents and split stories.

Indeed, all of these intermediaries are in the business of matching consumers with products. Trouble is, prior to visiting an intermediary, consumers are interested only in some products, which may not necessarily be the ones that yield the highest margins for the intermediary. If the latter was offering a perfect information service (i.e. one that enabled consumers to find what they want most quickly and efficiently), it would be losing valuable potential revenues. Hence the incentive to attract users with products that they want a priori and then divert them towards products that they might be interested in ex-post (i.e., once there).

Thus, consumers coming to the supermarket to buy daily staples (say, bread and milk) might be induced to also get expensive chocolate if they have to walk past the corresponding aisle anyway. Shoppers visiting a mall for its anchor store (say, Macy's) may decide to stop by a small design store while walking around the mall. And while flipping through the pages of a magazine in search of the article promised on the cover, readers are exposed to advertising, which produces most of the revenues. right – yet it will be displayed on the second search page only.]