Laws of Persuasion Physics
Momentum Must Build
Never plateau or drop energy.
Energy in your ad can only go in one direction: up. The moment intensity drops — even slightly — the viewer's brain registers "it's winding down" and starts looking for the exit. Momentum isn't just nice to have. It's the physics of attention.
Why This Works
The brain uses rate of change to predict what comes next. Increasing intensity signals "the best part is still coming." Decreasing intensity signals "the best part already happened." Once the brain makes that prediction, it's nearly impossible to re-engage. You get one trajectory.
In Your Ads
Plot the emotional intensity of your ad, section by section. If any point dips below the previous one, you have a momentum problem. The fix isn't always adding drama — sometimes it's cutting a section that dilutes energy. A shorter, escalating ad beats a longer one that peaks in the middle.
When This Breaks
Your ad hits a high point at the 10-second mark, then settles into a calm feature walkthrough. Completion rate drops off a cliff at exactly the moment energy dipped.
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