We're much more likely to think that something has improved in a ranked list if it goes from 11 to 10, than from 10 to 9, which doesn't actually make sense, given that 9 is a better position to be in than 10.
otherwise chaotic amount of choice. Naturally, a product or service’s position in such lists is powerful in determining consumer choice (Sorensen, 2007), and also how our choices are affected when a product’s rank also changes (Pope, 2009).
But even so, given our limited capacity to juggle more than six items at any one time (Kaufman, 1949), we tend to chunk such lists into smaller, more manageable sub-groups (Miller, 1956).
Fascinatingly, by creating these smaller sub-groups, we tend to embrace the similarities of any items within the group, and accentuate the differences with any items sitting outside, even though these items clearly haven’t changed at all! A good example is an experiment done on the perception of 12 cities, six of which had a state border, and six which didn’t. Those cities separated by a border were perceived to be further away from one another than those without a border (Maki, 1982).
The Top-Ten Effect is incredible because it suggests that we place heavy emphasis on very specific sub-grouping of lists, ending in a 5 or 0. It’s thought this is because such numbers are both easy to work with and also very common in our everyday lives. This natural need to categorise is something we crave, and we can’t stop it.