Diagnostic question · Hooked
Time to bring in the next user
Measures the time from a user's sign-up to the sign-up of someone they invited, and which actions involve others.
Spread
Plain label: viral cycle question
How long from a user's sign-up to the sign-up of someone they invited, and which everyday actions naturally involve other people?
Limits
What we don’t claim
- The Hook Model is a practical design tool, not a validated or complete theory of behavior.Hooked, Introduction
Sources
Hooked · Nir Eyal
Ch.1
Source IDs: HK-Q119HK-MON04
Book content is paraphrased, never quoted at length. Last verified October 24, 2026.
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