Decoy effect
(reading time – 30 sec.)

A phenomenon in marketing where consumers have a specific change in preference between two choices after being presented with a third choice.

An old Economist advertisement example clearly explains it.

The ad featured three subscription levels: $59 for online only, $159 for print only, and $159 for online and print. Ariely figured out that the option to pay $159 for print only exists so that it makes the option to pay $159 for onlineand print look more enticing than it would if it was just paired with the $59 option.

Topic: #CognitiveBiases
Source: Wikipedia