| name | hooked-model |
| description | Design habit-forming products using the Hook cycle. Use when building engagement loops, improving retention, designing notifications, or creating products users return to without external prompting. |
Hooked Model - Building Habit-Forming Products
The Hooked Model is a four-phase framework by Nir Eyal for creating products
that form user habits. A habit is formed when users engage with a product
repeatedly without conscious thought, driven by internal triggers rather than
external marketing.
When to Use This Skill
- Designing user engagement loops
- Improving product retention metrics
- Planning notification and re-engagement strategies
- Building features that create lasting habits
- Evaluating competitor engagement mechanisms
- Auditing ethical implications of engagement design
Core Concepts
The Hook Cycle
+-----------------+
| |
v |
TRIGGER |
(Internal/External) |
| |
v |
ACTION |
(Simple behavior) |
| |
v |
VARIABLE REWARD |
(Unpredictable) |
| |
v |
INVESTMENT |
(User effort)-------+
Phase 1: Trigger
External Triggers (initial hooks):
- Push notifications
- Email reminders
- Advertising
- Word of mouth
- Social media mentions
Internal Triggers (goal state):
- Boredom → Open TikTok
- Loneliness → Check Instagram
- Uncertainty → Google it
- FOMO → Check Slack
Phase 2: Action
The simplest behavior in anticipation of reward.
Fogg Behavior Model alignment:
B = MAT (Behavior = Motivation + Ability + Trigger)
For habit formation:
- Motivation: Must exist (desire for reward)
- Ability: Must be HIGH (action must be easy)
- Trigger: Must be present
| Product | Trigger | Simplest Action |
|---|
| Twitter | Boredom | Scroll feed |
| Google | Question | Type query |
| Instagram | FOMO | Open app |
| Slack | Anxiety | Check messages |
Phase 3: Variable Reward
Three types of variable rewards:
| Type | Description | Example |
|---|
| Tribe | Social validation | Likes, comments, follows |
| Hunt | Material resources | Search results, deals, information |
| Self | Personal achievement | Completing tasks, mastery, progress |
Why "Variable"? Predictable rewards lose power. Slot machines use variable
rewards - you never know which pull wins. Social feeds use the same psychology.
Phase 4: Investment
User puts something into the product that:
- Improves the product for them
- Increases likelihood of return
- Creates switching costs
| Investment Type | Example | Lock-in Effect |
|---|
| Data | Preferences, history | Personalization improves |
| Content | Posts, uploads | Social capital |
| Followers | Audience built | Network effects |
| Learning | Skills developed | Competency |
| Reputation | Reviews, karma | Identity |
Analysis Framework
Step 1: Map Current Hook
Your Product's Hook:
TRIGGER
External: _____________________
Internal (goal): _______________
ACTION
What's the simplest action? _______________
How many steps/taps? _______________
VARIABLE REWARD
Type: [ ] Tribe [ ] Hunt [ ] Self
What's unpredictable? _______________
INVESTMENT
What do users put in? _______________
How does it improve experience? _______________
Step 2: Identify Weak Links
Rate each phase (1-5):
| Phase | Score | Improvement Needed |
|---|
| Trigger strength | [/5] | |
| Action simplicity | [/5] | |
| Reward variability | [/5] | |
| Investment depth | [/5] | |
Step 3: Design Improvements
Focus on the weakest phase first. A hook is only as strong as its weakest link.
Output Template
## Hook Analysis
**Product:** [Name] **Date:** [Date] **Goal:** [Habit to form]
### Current Hook Cycle
**Trigger:**
- External: [Current external triggers]
- Internal target: [Emotion/situation → product]
**Action:**
- Current: [Steps to engage]
- Friction points: [Obstacles]
**Variable Reward:**
- Type: [Tribe/Hunt/Self]
- Variability source: [What changes]
**Investment:**
- Current: [What users contribute]
- Lock-in created: [Switching cost]
### Weakness Assessment
| Phase | Score (1-5) | Issue |
| ---------- | ----------- | ----- |
| Trigger | | |
| Action | | |
| Reward | | |
| Investment | | |
### Improvement Plan
1. **Trigger improvement:** [Specific change]
2. **Action simplification:** [Reduce steps to X]
3. **Reward enhancement:** [Add variability via]
4. **Investment deepening:** [New investment type]
### Ethical Check
- [ ] Product genuinely improves user's life
- [ ] User would recommend to friends
- [ ] We'd be comfortable if usage was public
- [ ] No dark patterns employed
Real-World Examples
Example 1: Instagram
| Phase | Implementation |
|---|
| Trigger | External: notifications. Internal: boredom, FOMO |
| Action | Open app, scroll (one tap) |
| Variable Reward | New posts (Hunt), likes/comments (Tribe) |
| Investment | Followers, posts, profile, DM history |
Example 2: Slack
| Phase | Implementation |
|---|
| Trigger | External: @mentions. Internal: anxiety about missing info |
| Action | Check channel (one click) |
| Variable Reward | New messages (Hunt), recognition (Tribe) |
| Investment | Channel history, integrations, workflows |
Example 3: Duolingo
| Phase | Implementation |
|---|
| Trigger | External: streak reminders. Internal: guilt, achievement |
| Action | Complete one lesson (5 min) |
| Variable Reward | XP, leaderboard (Self + Tribe) |
| Investment | Streak, progress, course completion |
Ethical Considerations
The Manipulation Test
Ask yourself:
- Materially improves life? Does the habit genuinely help users?
- User is the customer? Or are they the product?
- Would you use it yourself? And let your children use it?
- Transparent? Would users feel manipulated if they knew?
Ethical Spectrum
Facilitator -------- Entertainer -------- Dealer
(Helps users) (Neutral) (Exploits users)
Your product should be a Facilitator
Best Practices
Do
- Start with internal trigger research (what emotion leads to use?)
- Make first action as simple as possible
- Vary rewards meaningfully, not randomly
- Ensure investments create genuine value
- Test hook cycle with real users
Avoid
- Relying solely on external triggers (expensive, unsustainable)
- Complex actions that require learning
- Predictable rewards that become boring
- Investments that feel like manipulation
- Ignoring ethical implications
Integration with Other Methods
| Method | Combined Use |
|---|
| Fogg Behavior Model | Action phase design |
| Self-Initiated Triggers | Internal trigger development |
| Loss Aversion | Investment and streak psychology |
| Jobs-to-be-Done | Understanding underlying motivations |
Resources
