Social proof is public social engagement that other users can see. This includes likes, comments, and shares of an ad. It can also include award wins, reviews, and other forms of press engagement. These interactions can matter just as much as the ad copy when it comes to building trust and credibility. When a user is deciding whether or not to engage with an ad on Facebook, one of the considerations is if people previously engaged with the ad before they saw it. This is the power of social proof in action.
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Some form of social proof should be applied to all ads, whether it’s a number of how many have bought your product, a review rating, reference to an award win, or a press snippet. This can be included within the description of the ad, or for best results, overlaid on top of your image for maximum visibility. Be mindful that the social proof you’re using should be relevant to your target audience.