When we don't know what to do, we look at what others do.
You're looking for a restaurant on a street you don't know. One is empty, the other has a line outside. You end up going to the one with the line. We assume that people in our reference group have information we don't, especially in uncertain situations.
A Facebook experiment with more than 46,000 users compared two identical security prompts. One simply invited users to turn on extra security options; the other added how many friends in the user's network had already turned them on. Showing that social data increased security settings exploration by 37%, compared with the prompt that lacked that information.
In one of our own projects, the same mechanism worked in reverse. Showing female role models in a financial institution's leadership postings increased women's applications for leadership roles by 49%, without affecting men's applications.
In an uncertain situation, what others do works as an information shortcut. If a lot of people choose something, we assume they've already evaluated what we don't have time to evaluate ourselves.
Source: Das, S., Kramer, A., Dabbish, L. & Hong, J. (2014). Increasing Security Sensitivity With Social Proof: A Large-Scale Experimental Confirmation. CCS '14: Proceedings of the 2014 ACM SIGSAC Conference on Computer and Communications Security, 739-749.
Showing how many people have already completed a process, are already using a service, or have already applied for a position is one of the cheapest and most underused levers in institutional communication across Latin America.
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