All plays
When to use it
When popular products have real concurrent demand (active carts, recent orders, viewers) that shoppers can't see.
How to run it
Show a live demand signal on the product page, such as 'In 12 carts' or 'Ordered 34 times today', only on items where the true number is impressive.
Why it works
Give a reason to act now
Demand cues combine social proof with implied scarcity. Etsy A/B tested 'In X carts' on product pages and rolled it out, moving it even higher on the page (GoodUI leak). Weak numbers backfire: Airbnb rejected a '39% booked' stat that felt low.
Source: GoodUI leaks: Etsy 'In X carts', Airbnb