Metric · Hooked
Investment rate
Share of sessions in which the user invests something that improves the product with use (content, data, follows, reputation, skill), plus the share of new users who invest in their first session. A leading Return proxy.
Plain label: sessions where users put something inAlso known as: stored-value actions, first-session investment
Valid evidence for the investment link; activation or first-booking rates are not. Check that the ask comes after a reward: investment demanded before the first win loses users at the ask. HK-INV01 (Hooked Ch.5)
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.5
Source IDs: HK-INV01HK-INV19HK-Q107
Book content is paraphrased, never quoted at length. Last verified October 24, 2026.
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