Social Proof
When people are unsure, they do what they see others doing.
What it is
Uncertainty makes other people's behaviour the most useful signal available. Numbers of users, reviews, logos, ratings and "people also bought" all work because they answer the question a visitor cannot answer alone: is this normal, safe and worth it? The closer the others are to the visitor, the stronger the pull.
The research
In a line-length judgement task, participants gave an obviously wrong answer about a third of the time when a group of confederates had given it first.
Asch, 1951
How to use it
Be specific
"Trusted by 2,400 Sydney builders" beats "trusted by thousands". Specificity reads as truth.
Match the proof to the visitor
A plumber wants to see plumbers. Segment testimonials and logos by the industry of the page.
Show the behaviour, not the claim
"14 people booked this week" is proof. "Popular" is a label.
Put proof next to the ask
A testimonial beside the form outperforms a testimonial section three screens above it.
Related
Sources that shaped this entry: Digital Psychology, growth.design, Kolenda.io.