THE LEAD
Most short-form video scripts die at the same spot.
Watch time falls off a cliff right at the 30-second mark, across creators and niches. The drop is structural.
Short-form algorithms decide amplification off the early-frame retention. Lose the viewer at 30 seconds and reach gets capped at the audience you already have.
THE FRAMEWORK
The 90-second rule is the structure that survives the cliff. Four pieces:
1. The 3 beats. Hook, tension, payoff. Anything else is decoration. The full breakdown walks through why adding beats past 3 dilutes the one that matters.
2. The hook-to-payoff ratio. One-third hook and setup, two-thirds payoff. Invert the ratio and the retention curve looks like a cliff because the audience leaves while you're still setting up.
3. The watched-vs-scrolled test. At second 5, can a viewer summarize the payoff in one sentence? If yes, you've earned the next 85. If no, the algorithm stops feeding it before second 30.
4. The 90-second cap. Past 90 seconds, the audience expectation flips from stop-the-scroll to watch-a-thing, and the retention curve changes. If a script runs long, the cut goes in the middle. The hook and payoff stay.
BEFORE YOU DEPLOY
Run the 5-second summary test on your next script before you film it.
Read the first 5 seconds aloud. Can someone who's never seen it tell you the payoff in one sentence?
If the answer is no, the script opens with setup instead of signal. Move the payoff signal to the front and push the setup into the back half, after the audience has committed.
The opening line carries the payoff. The setup supports it.
THIS WEEK ON PROFESSOR LEADS
Mon: The 30-second cliff.
Tue: The 3 beats.
Wed: The hook-to-payoff ratio.
Thu: The watched-vs-scrolled test.
Fri: The 90-second cap.
Sat: TikTok-only wrap on the week.
William DeCourcy, Professor Leads