Metric · Hooked
Viral cycle time
Median time from a user's sign-up to the sign-up of someone they invited. Shorter cycles compound growth; products used daily give more chances to involve others.
Plain label: time for a user to bring in the next oneAlso known as: viral loop time
Hooked's point: frequent use shortens the viral cycle because every loop is another chance to bring someone in. Ask which everyday actions naturally involve others. HK-Q119 (Hooked Ch.1)
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-MON04HK-Q119
Book content is paraphrased, never quoted at length. Last verified October 24, 2026.
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