product-ux-expert

# Product UX Expert

## Core Principles

- **Reduce Cognitive Load** — Minimize mental effort required for every interaction
- **Accessibility First** — WCAG 2.2 AA is the baseline, not an afterthought
- **Evidence-Based** — Decisions backed by user research, not assumptions
- **Anticipatory Design** — Predict user needs before they ask
- **Ethical Design** — No dark patterns, transparent data practices
- **Mobile First** — Design for smallest screens, enhance for larger

---

## Quick Reference

### Nielsen's 10 Heuristics

| # | Heuristic | Key Question |
|---|-----------|--------------|
| 1 | Visibility of System Status | Does the user always know what's happening? |
| 2 | Match System & Real World | Does it use familiar language and concepts? |
| 3 | User Control & Freedom | Can users easily undo or exit? |
| 4 | Consistency & Standards | Does it follow platform conventions? |
| 5 | Error Prevention | Does it prevent errors before they occur? |
| 6 | Recognition over Recall | Is information visible, not memorized? |
| 7 | Flexibility & Efficiency | Are there shortcuts for experts? |
| 8 | Aesthetic & Minimalist Design | Is every element necessary? |
| 9 | Help Users with Errors | Are error messages helpful and actionable? |
| 10 | Help & Documentation | Is help available when needed? |

---

## Cognitive Psychology

### Cognitive Load Types

```
Intrinsic Load     — Complexity inherent to the task itself
Extraneous Load    — Unnecessary complexity from poor design (eliminate this!)
Germane Load       — Mental effort for learning/understanding (support this)
```

### Key Laws

```
Hick's Law         — More choices = longer decision time
                   → Limit options to 5-7, use progressive disclosure

Miller's Law       — Working memory holds 7±2 items
                   → Chunk information, use visual grouping

Fitts's Law        — Larger, closer targets are easier to click
                   → Make primary actions big and accessible

Jakob's Law        — Users expect your site to work like others
                   → Follow established patterns

Von Restorff       — Different items are more memorable
                   → Highlight CTAs with contrast

Serial Position    — First and last items remembered best
                   → Put key info at start/end of lists
```

### Gestalt Principles

```
Proximity          — Close elements are perceived as groups
Similarity         — Similar elements are perceived as related
Continuity         — Eyes follow smooth lines and curves
Closure            — Mind completes incomplete shapes
Figure-Ground      — Elements seen as foreground or background
Common Region      — Elements in same area are grouped
```

---

## Heuristic Evaluation

### Process

```
1. Define scope         — What screens/flows to evaluate
2. Select evaluators    — 3-5 UX experts (80%+ issues found)
3. Independent review   — Each expert reviews alone
4. Apply heuristics     — Rate severity for each issue
5. Consolidate          — Merge findings, remove duplicates
6. Prioritize           — Rank by severity × frequency
7. Report               — Actionable recommendations
```

### Severity Rating

| Level | Severity | Description |
|-------|----------|-------------|
| 0 | Not a problem | Evaluator disagrees it's an issue |
| 1 | Cosmetic | Fix only if extra time available |
| 2 | Minor | Low priority, causes friction |
| 3 | Major | High priority, significant impact |
| 4 | Catastrophic | Must fix before release |

### Issue Template

```markdown
## Issue: [Brief Description]

**Heuristic:** #N - Name
**Severity:** 0-4
**Location:** Screen / Component / Flow

**Problem:**
What's wrong and why it matters to users.

**Evidence:**
Screenshot or recording link.

**Recommendation:**
Specific fix with before/after comparison.
```

---

## User Journey Mapping

### Journey Map Structure

```
┌─────────────────────────────────────────────────────────────────┐
│  PERSONA: [Name, Goals, Context]                                │
├─────────┬─────────┬─────────┬─────────┬─────────┬──────────────┤
│ Stage   │ Aware   │ Consider│ Purchase│ Use     │ Advocate     │
├─────────┼─────────┼─────────┼─────────┼─────────┼──────────────┤
│ Actions │ Search  │ Compare │ Signup  │ Onboard │ Share/Review │
├─────────┼─────────┼─────────┼─────────┼─────────┼──────────────┤
│ Touch-  │ Search  │ Website │ Checkout│ App     │ Social       │
│ points  │ Ads     │ Reviews │ Email   │ Support │ Email        │
├─────────┼─────────┼─────────┼─────────┼─────────┼──────────────┤
│ Emotions│   😐    │   🤔    │   😟    │   😊    │    😍        │
│         │ curious │ hopeful │ anxious │ relieved│  delighted   │
├─────────┼─────────┼─────────┼─────────┼─────────┼──────────────┤
│ Pain    │ Too many│ Info    │ Complex │ Unclear │ No referral  │
│ Points  │ options │ overload│ forms   │ next    │ program      │
├─────────┼─────────┼─────────┼─────────┼─────────┼──────────────┤
│ Opportu-│ Clear   │ Compare │ 1-click │ Progress│ Share        │
│ nities  │ tagline │ table   │ signup  │ tracker │ incentive    │
└─────────┴─────────┴─────────┴─────────┴─────────┴──────────────┘
```

### Touchpoint Analysis

```
For each touchpoint, evaluate:

1. Entry Point      — How do users arrive?
2. User Goal        — What are they trying to accomplish?
3. Friction         — What slows them down?
4. Emotion          — How do they feel?
5. Drop-off Risk    — Where might they abandon?
6. Opportunity      — How can we improve?
```

---

## Accessibility (WCAG 2.2 AA)

### POUR Principles

```
Perceivable     — Can users perceive the content?
                  ✓ Text alternatives for images
                  ✓ Captions for video
                  ✓ 4.5:1 color contrast
                  ✓ Resizable text (up to 200%)

Operable        — Can users operate the interface?
                  ✓ Keyboard accessible
                  ✓ No keyboard traps
                  ✓ Skip navigation links
                  ✓ Sufficient time limits