🎲 Variable Rewards:
Giving unexpected treats to keep people engaged.
Variable rewards (such as spinning a wheel to unlock a prize), often motivate users more than predictable ones.
The unpredictability of not knowing what you'll get next, is exciting, and allows the user to imagine all the many things that it could be.
That moment of 'opening' your reward becomes addictive.
This theory was popularised by Nir Eyal, in his book Hooked.
It explains why the TikTok feed is so addictive—because you never know what the next scroll will show you.
"The next video might be really good".
It turns TikTok into a variable-reward slot machine.
✅ Habits
Variable rewards are incredibly useful in creating habits—they're addictive.
✅ Effort & motivation
You may find yourself unexplainably motivated to continue scrolling on TikTok.
✅ Perception of value
The unpredictability of variable rewards can distort (in a good way) the value of doing that action.
e.g., a slot machine has a negative expected value (you lose more than you win), but you can convince yourself that you "just need one big win to be up massively".
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