Design of Everyday Things Framework

Foundational design principles for creating products that are intuitive, discoverable, and understandable. The "bible of UX" — applicable to physical products, software, and any human-designed system.

Core Principle

Good design is actually a lot harder to notice than poor design, in part because good designs fit our needs so well that the design is invisible. When something works well, we take it for granted. When it fails, we blame ourselves — but the fault is almost always in the design.

The foundation: Design must bridge the gap between what people want to do and what the product allows them to do. The best designs are discoverable (you can figure out what to do) and understandable (you can figure out what happened).

Scoring

Goal: 10/10. When reviewing or creating designs, rate 0-10 based on discoverability, understandability, and error prevention. A 10/10 means users can figure out what to do without instructions, understand what happened, and recover from errors easily. Always provide current score and improvements to reach 10/10.

The Two Gulfs

Every interaction with a product requires bridging two gulfs: