Law of Prototypicality

What it is

In the book's framing, attributes that describe the category attract higher scores than less typical attributes. The regularity sits beside the book's separation of differentiation, a reason to prefer a brand, from distinctiveness, a means of being identified. Sharp argues that brands should build distinctive cues such as colours and shapes that identify them without carrying a message.

In effect

Read together with experiments on design, the regularity fits a wider pattern in which what is typical of a category is easy to recognise and tends to be liked. A 2006 study found that prototypical patterns were categorised faster and rated more attractive, and a 2011 study found that closeness to an average car design improved sales forecasts. Those studies concern patterns and cars, so linking them to the law is an interpretation made in the article on banks and technology brands choosing blue.

What it does not say

The law is stated in a marketing-science book and is held here as an argument from that book. The vault records that the book supports it with a small amount of data, so it is not treated as a tested finding of its own, and it does not say that a category colour is chosen for any particular reason.

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