Social proof
Evidence that other people value you — testimonials, reviews, user counts, mentions — used to build trust with new audiences.
Social proof is the signal that other people already trust you: testimonials, reviews, screenshots of praise, follower or customer counts, press mentions. People take cues from the crowd, so showing that others are on board lowers the bar for someone new to give you a chance.
On social it's often most persuasive when it comes from your audience rather than you — user-generated content and a credible influencer mention carry more weight than self-promotion because the endorsement isn't yours to make.
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