# Fogg Behavior Model
The Fogg Behavior Model, developed by [[BJ Fogg]] at Stanford's Behavior Design Lab, states that behavior occurs when three elements converge simultaneously: **Motivation** (desire to act), **Ability** (capacity to act), and **Prompt** (trigger to act). Expressed as **B = MAP**, the model explains why behaviors happen—or fail to happen. If any element is missing or insufficient, the behavior won't occur. A person might be highly motivated to exercise but lack ability (no gym access) or prompt (no reminder). The model provides a diagnostic framework: when a behavior isn't happening, identify which element is weak.
The key insight is that **ability often matters more than motivation**. Motivation fluctuates and is hard to sustain, but making behaviors easier (reducing [[Friction]]) produces more reliable change. Fogg's [[Tiny Habits]] method applies this: shrink the behavior until ability is trivially high, then motivation barely matters. The model also reveals why [[Persuasive Technology]] works—apps succeed by making behaviors easy (one-click) and providing timely prompts (notifications). For [[Behavioral Design]], the order of intervention should be: first ensure prompts exist, then maximize ability, then boost motivation only if needed.
## The Model Visualized
```
┌─────────────────────────────────────────────────────────────┐
│ FOGG BEHAVIOR MODEL: B = MAP │
├─────────────────────────────────────────────────────────────┤
│ │
│ Motivation │
│ (High) │ │
│ │ ┌─────────────────────────────────────┐ │
│ │ │ │ │
│ │ │ PROMPTS SUCCEED HERE │ │
│ │ │ (Behavior happens) │ │
│ │ │ │ │
│ │────┼─────────────────────────────────────│ │
│ │ │ ACTION LINE │ │
│ │────┼─────────────────────────────────────│ │
│ │ │ │ │
│ │ │ PROMPTS FAIL HERE │ │
│ │ │ (Behavior doesn't happen) │ │
│ │ │ │ │
│ (Low) │ └─────────────────────────────────────┘ │
│ └──────────────────────────────────────────► │
│ (Hard) Ability (Easy) │
│ │
│ When M × A is above the action line, a prompt triggers │
│ behavior. Below the line, prompts fail. │
│ │
│ KEY: It's often easier to increase ABILITY than │
│ MOTIVATION. Make the behavior smaller/easier. │
│ │
└─────────────────────────────────────────────────────────────┘
```
## The Three Elements
| Element | Description | Sub-components |
|---------|-------------|----------------|
| **Motivation** | Desire to perform behavior | Pleasure/pain, hope/fear, acceptance/rejection |
| **Ability** | Capacity to perform behavior | Time, money, effort, mental load, routine fit |
| **Prompt** | Trigger that calls to action | Person prompts, context prompts, action prompts |
## Motivation Sources (Fogg)
| Motivator | Dimension |
|-----------|-----------|
| **Sensation** | Pleasure ↔ Pain |
| **Anticipation** | Hope ↔ Fear |
| **Social** | Acceptance ↔ Rejection |
## Ability Factors (Simplicity Chain)
| Factor | Question |
|--------|----------|
| **Time** | Do I have time? |
| **Money** | Can I afford it? |
| **Physical effort** | Is it physically demanding? |
| **Mental effort** | Is it cognitively hard? |
| **Social deviance** | Is it socially acceptable? |
| **Routine** | Does it fit my current habits? |
## Types of Prompts
| Type | Description | Example |
|------|-------------|---------|
| **Spark** | High ability, low motivation | Inspirational video |
| **Facilitator** | High motivation, low ability | Step-by-step guide |
| **Signal** | High motivation, high ability | Simple reminder |
## Applying the Model
| If Behavior Doesn't Happen... | Intervention |
|------------------------------|--------------|
| **No prompt** | Add a trigger |
| **Low ability** | Make it easier, reduce friction |
| **Low motivation** | Connect to core motivators |
| **Competing behaviors** | Remove or weaken them |
## Design Sequence (Fogg's Recommendation)
```
1. CHECK PROMPT → Does a trigger exist at the right moment?
↓
2. MAXIMIZE ABILITY → Can you make the behavior easier?
↓
3. BOOST MOTIVATION → Only if steps 1-2 aren't sufficient
```
## B=MAP vs Other Models
| Model | Focus |
|-------|-------|
| **Fogg (B=MAP)** | M × A × P must converge |
| **COM-B** | Capability, Opportunity, Motivation |
| **Transtheoretical** | Stages of readiness |
| **[[Nudge Theory]]** | Choice architecture |
## Examples
| Behavior | Motivation | Ability | Prompt |
|----------|------------|---------|--------|
| **Flossing** | Moderate (health) | Low (takes time) | After brushing |
| **Instagram** | High (social) | Very high (one tap) | Notification |
| **Exercise** | Variable | Low (effort, time) | Gym clothes visible |
| **Reading** | Moderate | Depends on access | Book on nightstand |
## Tiny Habits Application
| Traditional | Tiny Habits (B=MAP) |
|-------------|---------------------|
| "Exercise 30 min" | "2 pushups after bathroom" |
| High motivation needed | Ability maxed, motivation irrelevant |
| Often fails | Consistently succeeds |
## Key Insights
| Insight | Implication |
|---------|-------------|
| **Motivation is unreliable** | Don't depend on it |
| **Ability is underrated** | Make behaviors tiny |
| **Prompts must be timely** | Right moment matters |
| **All three required** | Missing one = no behavior |
| **Order matters** | Prompt → Ability → Motivation |
## References
- Fogg, BJ. *[[Tiny Habits]]* (2019)
- Fogg, BJ. "A Behavior Model for Persuasive Design" (2009)
- https://behaviormodel.org/
- Stanford Behavior Design Lab
## Related
- [[BJ Fogg]]
- [[Tiny Habits]]
- [[Behavior Change]]
- [[Behavioral Design]]
- [[Friction]]
- [[Environment Design]]
- [[Habit Formation]]
- [[Persuasive Technology]]
- [[Nudge Theory]]
- [[Motivation (MoC)|Motivation]]
- [[Atomic Habits]]