---
name: wondelai/hooked-ux
source: https://app.decimal.ai/s/wondelai-hooked-ux@1/SKILL.md
source_sha256: 258df66808aa
---

# Hook Model Framework

Framework for building habit-forming products. Habits are not created — they are built through successive cycles through the Hook.

## Core Principle

**The Hook Model** = a four-phase loop that connects the user's problem to your solution frequently enough to form a habit, moving usage from deliberate to automatic.

```
Trigger → Action → Variable Reward → Investment
    ↑                                      │
    └──────────────────────────────────────┘
```

## Scoring

**Goal: 10/10.** When reviewing or creating product engagement mechanics, score the loop by the four Quick Diagnostic rows (internal trigger, dead-simple action, variable reward, investment loads next trigger): each row earns 2 (fully satisfied), 1 (partial), or 0 (absent), then `score = round(total / 8 × 10)`. Then apply the ethics gate: if the Manipulation Matrix places the product as Dealer (or it hits any "When NOT to Use" condition), cap the score at 3 regardless of mechanics. Bands: 9-10 = complete loop, internal trigger identified, ethics clear; 5-6 = loop runs but leans on external triggers or predictable rewards; <=3 = broken loop or extractive design. Always state the current score and the specific diagnostic rows blocking 10/10.

## The Four Phases

### 1. Trigger

**Core concept:** The actuator of behavior. Triggers are external (environment-driven: notifications, emails, ads) or internal (emotion-driven) — and the goal is to migrate users from external to internal triggers.

**Why it works:** Every habit starts with a cue. External triggers get users started, but internal triggers — boredom, loneliness, uncertainty, FOMO — drive unprompted usage because the emotion itself fires before any reminder can.

**Key insights:**
- Map your product to the specific negative emotion it resolves (boredom, loneliness, confusion, FOMO)
- Effective external triggers are well-timed, actionable, and lead to the simplest possible next action
- If users still need external prompts after ~30 days, no internal trigger has formed

**Product applications:**

| Context | Application | Example |
|---------|-------------|---------|
| **Onboarding** | External triggers establish the first loop | Welcome email with one clear action |
| **Retention** | Map product to internal emotional trigger | Instagram resolves boredom; Google resolves confusion |
| **Re-engagement** | External triggers bridge gaps until habit forms | Push: "Your friend just posted a photo" |

**Copy patterns:**
- "Don't miss what happened while you were away" (FOMO trigger)
- "Your friend just..." (social trigger bridging to internal)
- "Pick up where you left off" (routine trigger)

**Ethical boundary:** Don't build triggers that fire on vulnerable emotional states (depression, addiction, grief) — those users can't exercise the autonomy the loop assumes.

See [references/triggers.md](references/triggers.md) when mapping triggers — the emotion-to-product mapping exercise and the external-to-internal transition plan.

### 2. Action

**Core concept:** The simplest behavior done in anticipation of a reward, guided by the Fogg Behavior Model: Behavior = Motivation + Ability + Trigger, all converging at the same moment.

**Why it works:** Increasing motivation is hard and unreliable; reducing friction (increasing ability) is easier and more effective. Every extra step, field, or decision is a drop-off point.

**Key insights:**
- Six elements of simplicity: time, money, physical effort, brain cycles, social deviance, non-routine
- The action is the simplest behavior in anticipation of reward — not the full task
- Hick's Law: more choices = slower decisions; reduce options to increase action rate

**Product applications:**

| Context | Application | Example |
|---------|-------------|---------|
| **Signup flow** | Minimize fields and steps | One-click Google/Apple sign-in |
| **Core action** | Completable in seconds | Twitter: type 280 characters and post |
| **Progressive disclosure** | Ask for more only after initial reward | Duolingo: play first, create account later |

**Copy patterns:**
- "Just one tap to..." (emphasizes simplicity)
- "No credit card required" (money/risk simplicity)
- Buttons should be verbs: "Post", "Save", "Share" — not "Submit" or "Continue"

**Ethical boundary:** When you simplify an action, don't strip the cost or consequence with it — a one-tap purchase must still surface the price and the commitment.

See [references/product-applications.md](references/product-applications.md) when adapting the loop to your context — action and investment patterns for B2B SaaS, e-commerce, health, and productivity tools.

### 3. Variable Reward

**Core concept:** The phase that keeps users coming back. Anticipation of reward — not the reward itself — creates dopamine, and rewards must be variable (unpredictable) to sustain engagement.

**Why it works:** The brain's dopamine system responds most strongly to anticipation of uncertain rewards — the slot machine effect. Three reward types — tribe (social), hunt (resources), self (mastery) — tap fundamental human drives.

**Key insights:**
- Tribe = social validation; Hunt = search for resources/information; Self = personal mastery
- Predictable rewards lose power; finite variability eventually becomes predictable — aim for infinite variability
- Autonomy is critical: users must feel in control; forced engagement backfires

**Product applications:**

| Context | Application | Example |
|---------|-------------|---------|
| **Social features (Tribe)** | Variable social validation | Instagram likes — you never know how many |
| **Content feeds (Hunt)** | Unpredictable resource stream | Infinite scroll with algorithmically varied content |
| **Gamification (Self)** | Accomplishment with variable difficulty | Duolingo streaks + surprise bonus challenges |

**Copy patterns:**
- "See what's new" (implies variability)
- "3 people responded to your post" (tribe reward, variable quantity)
- "You've unlocked a new achievement!" (self reward, unexpected)

**Ethical boundary:** If users consistently feel worse after engaging (regret, time loss, anxiety), the reward system is extractive — avoid infinite scroll without natural stopping points.

See [references/rewards.md](references/rewards.md) when designing a reward — tribe/hunt/self patterns, the four reinforcement schedules, and reward timing. For the dopamine/anticipation mechanism behind variable rewards, see [references/neuroscience-foundations.md](references/neuroscience-foundations.md).

### 4. Investment

**Core concept:** Users invest something — time, data, effort, social capital, money — that improves the product for next use, raises switching costs, and loads the next trigger.

**Why it works:** People value what they put effort into (the IKEA effect). Investment is not about immediate reward — it improves the next cycle, creating a self-reinforcing loop.

**Key insights:**
- Investment should come after reward, not before — users invest when they feel good
- Each investment should load the next trigger (posting content triggers reply notifications)
- Small investments compound: preferences → better recommendations → more usage; stored value grows over time

**Product applications:**

| Context | Application | Example |
|---------|-------------|---------|
| **Data investment** | History improves personalization | Spotify: more listening = better recommendations |
| **Content investment** | User-created content they won't abandon | Instagram posts, Notion documents |
| **Reputation/social investment** | Social capital that exists only on-platform | Airbnb host ratings, LinkedIn network |

**Copy patterns:**
- "Complete your profile to get better matches" (investment → future value)
- "The more you use it, the smarter it gets" (compound investment)
- "Invite your team to collaborate" (social investment)

**Ethical boundary:** Investment should genuinely improve the experience — never trap users with artificial switching costs or impossible data export; make staying the better choice through real value.

## The Habit Zone

Two axes determine if a product can become a habit:

| | Low Frequency | High Frequency |
|--|---------------|----------------|
| **High Perceived Value** | Viable product (needs ads/marketing) | **HABIT ZONE** |
| **Low Perceived Value** | Failure | Failure |

Ask: how often do users need to engage, what's the perceived value of each engagement, and is frequency high enough to form automatic behavior?

## Habit Testing

The 5% rule: a habit has formed when at least 5% of users show unprompted, habitual usage.

**Three questions:**
1. **Who are the habitual users?** Which users engage most frequently, and what do they share?
2. **What are they doing?** Identify the "Habit Path" — the action sequence that separates power users from casual users.
3. **Why are they doing it?** What internal trigger and emotion precede usage?

See [references/habit-testing.md](references/habit-testing.md) when running the test — cohort analysis, finding the Habit Path, and confirming the 5% threshold. For worked teardowns of these loops in real products (Instagram, Slack, Duolingo, Pinterest, and failures), see [references/case-studies.md](references/case-studies.md).

## The Manipulation Matrix

Framework for evaluating the ethics of habit-forming products:

|  | **Maker Uses Product** | **Maker Doesn't Use** |
|--|------------------------|----------------------|
| **Materially Improves User's Life** | **Facilitator** | **Peddler** |
| **Doesn't Improve Life** | **Entertainer** | **Dealer** |

Ask: would I use this myself? Does it genuinely help users achieve their goals? Am I exploiting vulnerabilities or serving needs?

### When NOT to Use the Hook Model

- Your product doesn't genuinely improve lives
- You're targeting vulnerable populations (children, addiction-prone users)
- The business model depends on user regret
- Engagement conflicts with user wellbeing

See [references/ethical-boundaries.md](references/ethical-boundaries.md) when the Manipulation Matrix flags a concern — dark-pattern catalog and how to protect vulnerable users.

### Regulatory Context

Watch emerging regulation: children's apps (COPPA, GDPR-K), dark patterns (rising FTC enforcement), "addictive" notification practices, and loot boxes (expanding gaming rules).

## Onboarding Audit Checklist

Optimizing onboarding for habit formation:

### First Trigger
- [ ] First action obvious and easy; right external trigger for this user
- [ ] Value proposition clear before asking for investment

### First Action
- [ ] Core action completable in under 60 seconds, friction removed
- [ ] UI familiar (no new learning required)

### First Reward
- [ ] Immediate feedback with a variable element (surprise, delight)
- [ ] Reward connects to an internal trigger

### First Investment
- [ ] Investment asked after reward (not before), small but meaningful
- [ ] Investment loads the next trigger

### Loop Completion
- [ ] Clear path back to the trigger; external triggers sent at appropriate times
- [ ] Progression through the Hook is measured

## Common Mistakes

| Mistake | Why It Fails | Fix |
|---------|-------------|------|
| **Relying on external triggers indefinitely** | You're renting attention, not building habits | Map product to an emotion; transition to internal triggers within 30 days |
| **Making the core action too complex** | Users drop off before the reward | Simplify to minimum viable action; apply the six ability factors |
| **Using predictable rewards** | Dopamine response fades with novelty | Add variability across tribe, hunt, and self rewards |
| **Asking for investment before reward** | Users haven't received value yet | Sequence: trigger, action, reward, THEN investment |
| **Ignoring the ethics of your hook** | User regret, backlash, regulatory risk | Use the Manipulation Matrix; be a Facilitator, not a Dealer |

## Quick Diagnostic

Audit any product feature:

| Question | If No | Action |
|----------|-------|--------|
| What's the internal trigger? | Users need reminders to use it | Research user emotions |
| Is the action dead simple? | Users start but don't complete | Remove friction |
| Is the reward variable? | Users get bored | Add unpredictability |
| Does investment load next trigger? | Users don't return | Connect investment to triggers |

## Further Reading

Based on the Hook Model developed by Nir Eyal:

- [*"Hooked: How to Build Habit-Forming Products"*](https://www.amazon.com/Hooked-How-Build-Habit-Forming-Products/dp/1591847788?tag=wondelai00-20) by Nir Eyal
- [*"Indistractable: How to Control Your Attention and Choose Your Life"*](https://www.amazon.com/Indistractable-Control-Your-Attention-Choose/dp/194883653X?tag=wondelai00-20) by Nir Eyal (companion: resisting unwanted habits and building focus)

## About the Author

**Nir Eyal** taught at Stanford Graduate School of Business and the Hasso Plattner Institute of Design, after working in the gaming and advertising industries where he saw habit psychology firsthand. *Hooked* distills that research into a framework used by product teams from startups to Fortune 500s; his follow-up *Indistractable* addresses resisting the same triggers.