The Zeigarnik Effect in Click-Through Rates

Russian psychologist Bluma Zeigarnik noticed something: Waiters remembered orders perfectly until they were served. Once completed, they forgot them. The Brain hates "Unfinished Tasks." It holds them in active memory.

Applying this to Ads (Open Loops)

If your ad tells the whole story, the user is satisfied. They scroll on. You need to open a loop and not close it.

Bad Ad: "Our vacuum cleans 99% of dust using suction." (Statement = Closed Loop). Good Ad: "The one spot in your house you are missing (and why it's making you sick)." (Question = Open Loop).

The only way to close the loop (and satisfy the brain's itch) is to Click.

Clickbait vs. Curiosity

Clickbait promises X and delivers Y. (Lie). Curiosity promises X and delivers X. (Truth). Use the Zeigarnik effect to drive the click, but pay it off immediately on the landing page.