Simple definition
This is a learning pattern where some actions are rewarded and some are not, but the user cannot predict which one will pay off.
Classic example
Slot machines. Most pulls do nothing, but some do, and that uncertainty keeps people engaged.
How it shows up online
Most videos may be mediocre, but a few are highly rewarding. That uneven reward pattern is enough to sustain compulsive scrolling.
What to do
The best defense is friction before the loop starts. Begin with breaking the scroll loop and TikTok vs Reels vs Shorts.