Alan Cooper - Interaction Design

Apply Cooper's Goal-Directed Design principles from "About Face" to create software that helps users achieve their goals without unnecessary friction.

Core Philosophy

Goal-Directed Design

Users don't want to use software - they want to accomplish goals. Design for the goal, not the task.

Test: For every feature, ask "What goal does this help the user achieve?" If you can't answer clearly, reconsider the feature.

Perpetual Intermediates

Most users are neither beginners nor experts - they're perpetual intermediates who:

• •Know the basics
• •Don't read manuals
• •Want to get things done efficiently
• •Will never use "advanced" features

Rule: Design for intermediates first. Beginners will learn. Experts will adapt.

Polite Software

Software should behave like a considerate human assistant:

• •Remembers user preferences
• •Doesn't ask the same question twice
• •Anticipates needs
• •Admits mistakes gracefully
• •Doesn't blame the user

Prescriptive Rules

Eliminate Excise

Excise = work users must do that doesn't directly advance their goal.

Modal vs Modeless

PREFER MODELESS:
- Let users work without interruption
- Don't trap users in dialogs
- Allow parallel activities

WHEN MODAL IS NECESSARY:
- Make it obviously modal (centered, backdrop, clear boundaries)
- Provide clear escape (X button, Escape key, backdrop click)
- Keep it focused on ONE decision
- Don't stack modals on modals

Dialog Design (Cooper's Rules)

/* Modals must be unmistakably modal */
dialog {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);  /* Centered = important */
  z-index: 1000;                      /* Above everything */
}

dialog::backdrop {
  background: rgba(0, 0, 0, 0.5);     /* Dim background = focus here */
}

Dialog Content Rules:

1. •Clear title stating the decision/action
2. •Minimal text - users don't read dialogs
3. •Primary action on the right (Western reading order)
4. •Cancel always available
5. •No "OK" - use verbs ("Save", "Delete", "Send")

Undo Over Confirmation

BAD:  "Are you sure you want to delete?" [Yes] [No]
GOOD: *deletes immediately* [Undo] (visible for 5 seconds)

WHY:
- Confirmation dialogs train users to click "Yes" without reading
- Undo respects user intent while allowing recovery
- Faster workflow, fewer interruptions

Smart Defaults

Every input should have a sensible default:
- Date picker: today's date
- Country: detected from browser
- Format: most common choice
- Quantity: 1

NEVER:
- Blank required fields when you could guess
- "Select one..." as default in dropdowns
- Default to destructive option

Progressive Disclosure

Level 1: Essential controls (always visible)
Level 2: Common options (one click away)
Level 3: Advanced options (settings/preferences)
Level 4: Power user features (keyboard shortcuts, CLI)

RULE: 80% of users use 20% of features.
      Make that 20% immediately accessible.

Persona Thinking

Before designing, define who you're designing for:

Primary Persona:
  name: "Regular User"
  goal: Complete task quickly
  behavior: Uses app weekly, knows basics
  frustration: Unnecessary steps, confusion

Secondary Persona:
  name: "Power User"
  goal: Maximum efficiency
  behavior: Daily use, keyboard shortcuts
  frustration: Missing features, forced mouse use

Negative Persona (don't design for):
  name: "Edge Case"
  behavior: Unusual workflow nobody else needs
  decision: Document limitation, don't add complexity

Review Checklist

Before shipping any interaction:

• • What user goal does this serve?
• • Is there excise that can be eliminated?
• • Would a perpetual intermediate understand this immediately?
• • Are modals truly necessary, or could this be modeless?
• • Do dialogs have verb buttons (not "OK")?
• • Is undo available instead of confirmation?
• • Are smart defaults provided?
• • Does the software remember user preferences?

Anti-Patterns

Cooper Score

Integration

Combine with:

• •/usability - Psychology of why Cooper's patterns work
• •/design - Visual simplicity that supports goal-directed design
• •/mobile - Form design that eliminates input excise