Nudge on the fly: Taco Bell's ordering kiosk

Cowry Authors • 2 min read

The other night one of our Cowry team members went to dinner at Taco Bell and decided to order from the self ordering kiosk. The ordering process was really simple and the kiosk itself was very easy to use. However, when they got to the end of the ordering process they were shocked to see the large upgrade option literally jumping off the screen. 

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The large option growing in size like that is an example of the behavioural science theory of saliency. Also by having the progress bar at the top of the page they are using another behavioural science theory: goal gradient. 

Goal gradient is the theory that states people are more likely to finish a task if it looks like we are close to completion. (Cryder, 2013) Having the progress bar shows people ordering how much more they have to do before their order is completed. This makes the process very unambiguous and also makes it more likely that they will complete their order. 

The theory of saliency says that the more salient an object on the page is the more likely people are to read, like, and remember that object. (Underwood, 2013) The saliency of an object is affected by size, visual hierarchy, and much more. People are drawn to the top of the page so having the large option above the regular option will make people look at the large option more. Having the large option moving out at you and increasing in size increases the saliency of the option and will make you focus more of your attention on the large option. 

One issue with this nudge is, how ethical is it to nudge people to get a bigger portion of food?  This nudge is ethical because the other option is still available to choose. Even though they made the focus of the page the large upgrade, the choice is still the customers to pick if they want the large or regular. They also do not try to trick or deceive people into picking the large option.

Taco Bell understands how to draw people into looking at an option. If people are on the fence about upgrading or not, having the large option be more salient will nudge people to choose the upgrade. 


Cryder, C. E., Loewenstein, G., & Seltman, H. (2013). Goal gradient in helping behavior. Journal of Experimental Social Psychology, 49(6), 1078-1083.

Underwood, G., & Foulsham, T. (2006). Visual saliency and semantic incongruency influence eye movements when inspecting pictures. The Quarterly journal of experimental psychology,59(11), 1931-1949.

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