Whatever contrasts with its surroundings captures our attention first.
We give more weight to whatever is novel, contrasts, or stands out from its surroundings. A color, a size, or even a word can be more salient than the rest and capture our attention before anything else.
The Canadian government wanted more citizens to renew certain services online instead of in person. It tested different mailed invitation cards, varying the envelope color and text to make them stand out more. The card that used the salience principle achieved 41.7% more online renewals, compared to invitations that didn't use it.
Our attention is a limited resource. Whatever contrasts with the rest of the environment gets processed first and with less effort, so we direct our attention there before deciding what to do with the rest of the information.
Source: Castelo, N., Hardy, E., House, J., Mazar, N., Tsai, C. & Zhao, M. (2015). Moving Citizens Online: Using Salience and Message Framing to Motivate Behavior Change. Behavioral Science & Policy, 1(2), 57-68.
Digital government procedures in Latin America usually compete for attention with dozens of other messages. Visually highlighting the right button or deadline, instead of leaving everything with the same visual weight, is one of the cheapest ways to increase action rates without changing the procedure itself.
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