Make stored value visible, and exportable

• Early fit and Scale × Return · Habit (utility-led)in season
• Early fit and Scale × Return · Partial habitin season
• Early fit × Returnin season
• Scale × Returnin season
• Scale × Staylead
• Mature and Stalled × Pay · Sales-led B2Bin season
• Mature and Stalled × Payin season
• Mature and Stalled × Stayin season

• Duolingo · 2022

  Round

  Duolingo: a streak with a safety valve

  Letting learners equip up to two Streak Freezes raised daily active learners by 0.38% (company A/B result, Jan 2022). Learners who reached a 7-day streak were 3.6x more likely to finish their course, a correlational figure.

  M4 ×ReturnStay
  NumberBLinkBCase grade for the number: B. Evidence grade for the mechanism link: B.CorrelationalCompany-reported

• Mint (Intuit) · 2024

  Round

  Mint: stored value didn't save it

  Mint shut down on March 23, 2024; Intuit pointed users to Credit Karma (NerdWallet). Many causes, chiefly the owner's strategy. The closure doesn't refute the mechanics; it shows they can't outweigh a business decision.

  M5 ×StartReturn
  NumberCLinkDCase grade for the number: C. Evidence grade for the mechanism link: D.Analyst inferenceMany causes

• Spotify · 2025

  Round

  Spotify Wrapped: identity as a reward

  200M+ engaged users in the first 24 hours of Wrapped 2025, 19% more than 2024 (which took 62 hours to reach 200M), and 500M+ shares, up 41% (Spotify, via TechCrunch, Dec 4, 2025). Company-reported.

  M4 ×ReturnSpread
  NumberBLinkDCase grade for the number: B. Evidence grade for the mechanism link: D.Analyst inferenceCompany-reported

• Starbucks · 2025

  Round

  Starbucks Rewards: stars, tiers and devaluation risk

  34.2M US 90-day active members, and member spend at 58% of US company-operated tender (data as of Sept 28, 2025; 60% a year earlier). The three-tier relaunch on March 10, 2026 drew mostly negative reaction from casual members (press).

  M4-M5 ×StayPay
  NumberBLinkDCase grade for the number: B. Evidence grade for the mechanism link: D.Analyst inferenceCorrelational

• TechniqueCLimitedEvidence grade C. Limited evidence: few or small studies.

  A first social reward from a real person, fast

  early, real encouragement

  Route a newcomer's first post, workout or project to real people who respond quickly, and show the value of the community in the first session rather than weeks later.

• TechniqueBModerateEvidence grade B. Moderate evidence: solid studies with some limits.

  Pay in recognition, not small cash

  recognition over money

  Don't attach small or rare cash to things people already do for social or personal reasons. Reward contribution with recognition, reputation and privileges that mean something, ideally given by peers, and if you pay, pay meaningfully.

• TechniqueBModerateEvidence grade B. Moderate evidence: solid studies with some limits.

  Minimum effective incentive

  smallest reward that still works

  For behaviors you want users to own, use the smallest incentive that still gets the behavior, announce up front when any launch bonus ends, and favor recognition over payment. Large rewards and threats buy compliance only while they last; small ones leave room for people to feel they chose.

• TechniqueCLimitedEvidence grade C. Limited evidence: few or small studies.

  Honest loss framing

  show what the user would lose

  When a real loss is at stake, frame the message around it: "$210 in credits expire on June 30; apply them to your next invoice", "On the free plan, 14 of your projects would become read-only." People respond more to a possible loss than to an equal gain, but only true, specific losses hold up.

• TechniqueDPractitionerEvidence grade D. Practitioner framework or anecdote: plausible, untested.

  Sunk Cost Prison (GT#50)

  visible stored value

  Users who have built up time, content, status or relationships keep going because leaving would waste it. Chou calls it possibly the strongest loss-based mechanism and a treacherous one; the product-friendly form makes stored value visible and portable, so staying is a choice.

• TechniqueBModerateEvidence grade B. Moderate evidence: solid studies with some limits.

  Recognition instead of pay for voluntary behavior (OCT-M11)

  social rewards over cash

  Before attaching cash or points to something users already do willingly (helping, creating, reviewing), check whether it will move them from a social frame to a transactional one. Chou's rules: don't pay for what people already love doing, avoid rewards so small they insult, and prefer thanks, visibility and gifts in kind.

Sources

• Hooked · Nir Eyal

  Ch.1 · Ch.5 · Ch.7

Source IDs: HK-INV27 · HK-INV29 · HK-MON06 · HK-INV32

Book content is paraphrased, never quoted at length. Last verified October 24, 2026.