Telling people a deal is almost gone made them want it more, not less

Robert Cialdini's scarcity principle holds that things become more desirable the moment they seem limited or about to disappear, largely out of fear of missing out rather than the item's actual usefulness. It's one of six influence principles he identified after three years going undercover in sales training, and it remains a staple of marketing built around 'limited time only' offers.

— Robert Cialdini, Influence: The Psychology of Persuasion — 1984
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