Current marketing strategy has shifted attention away from how consumers chose brands towards how they use products. Expanding the use of a product can have an enormous impact on sales. Inducing existing customers to use a product in a new context is also more cost effective than either soliciting non-users to try the product, or luring people away from the competition

Nearsightedness is to a large extend inherited; its incidence vary from one family to another. The reason behind the link between the common incidence of nearsightedness and high intelligence is unclear. Previous generations thought that eyes could become strained by years spent pouring over books, but a few decades ago the popular medical views was that nearsighted people gravitated towards the library because they find it hard to excel at sports. Recently there has been partial support for a theory that intelligence and nearsightedness may, in fact, be part of a genetic package