How Technology Hijacks People’s Minds

One major reason why is the #1 psychological ingredient in slot machines: intermittent variable rewards.
If you want to maximize addictiveness, all tech designers need to do is link a user’s action (like pulling a lever) with a variable reward. You pull a lever and immediately receive either an enticing reward (a match, a prize!) or nothing. Addictiveness is maximized when the rate of reward is most variable.

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