What problem does it solve? Users blame themselves when products confuse them, but the fault is almost always in the design. This Skill helps you diagnose why users make mistakes, why interfaces feel unintuitive, and how to fix discoverability, feedback, and error-prevention failures using Don Norman's foundational design principles. ## Core Features & Use Cases - Seven Design Principles: Apply affordances, signifiers, mappings, constraints, feedback, discoverability, and conceptual models to audit any physical or digital product. - Error Analysis: Classify slips and mistakes, then design constraints, undo, and clear error messages that prevent and recover from them. - Gulf & Stage Analysis: Bridge the gulfs of execution and evaluation using the seven stages of action framework. - Use Case: When users keep clicking the wrong button or abandoning a form, walk the interaction through the quick diagnostic checklist to pinpoint whether the failure is missing signifiers, poor mapping, or absent feedback, then apply the referenced fix patterns. ## Quick Start Ask the AI to audit your checkout flow using the Design of Everyday Things principles and score its discoverability, understandability, and error prevention out of 10.
