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Variable reward 0:54
A 54-second explainer of Variable reward, narrated over the same demo you can try yourself.
Try the interactive Variable reward demo
What this video covers
A variable reward is a payoff that comes unpredictably - sometimes big, sometimes nothing - rather than the same every time. That uncertainty is what makes it gripping: not knowing what you'll get, or when, drives far more repeated action than a predictable reward of the same average value. It's the engine behind slot machines, social feeds and the endless pull-to-refresh.
Notice how the unpredictable box kept pulling you back - "maybe this time" - while the fixed one you tapped once and were done. Same average payoff; only the uncertainty differed. That little hook of not-knowing is variable reward, and it's the most habit-forming pattern in your phone.