Zero Price Effect
A price drops to free. Demand doesn't rise a little. It jumps, even when the discount to get there was identical.
Applied behavioural science & economics
Probably without knowing it. And probably doing it badly.
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I'm Grant Burrow. I've spent years running behavioural experiments inside real consumer products, the kind written up as Harvard Business School case studies, not just textbooks. I care about the applied part: not reciting theory, but showing you the sign, the screen, the menu, and exactly why it works.