Why Simplicity Wins: The Psychology Behind Modular Design

In the article "A Brief Discussion on Modular Design (Part 1)", the author explores what modular design is and why it is needed, especially from the perspectives of time constraints and cognitive psychology.

Why Simplicity Matters

Designers often hear "keep it simple," not because simplicity is always best, but because irrelevant or distracting information hinders the main function. Users prefer simplicity because it reduces cognitive load and presents pure, unambiguous information.

Across clothing, architecture, industrial products, and UI design, simplicity enhances aesthetic appeal, usability, and learning efficiency.

Human Cognitive Limits

Our brains have limited capacity for processing information. When faced with excessive details, we feel frustration and fatigue.

Cognitive psychology studies how the brain processes information through sensors, processors, memory, and response mechanisms.

In 1956, Miller discovered the "magical number 7±2," indicating that short‑term memory can hold about seven chunks of information. Later research refined this to roughly four chunks for working memory.

Modular Design Makes Complexity Simple

By breaking down related information into modules, modular design reduces the number of chunks the brain must handle, speeding up information processing and lowering development costs.

Examples:

When planning a hot‑pot meal, categorizing ingredients (leafy greens, root vegetables, mushrooms, meat, spices) helps organize purchases and cooking.

In commercial products, the purchase flow can be divided into pre‑sale, sale, and post‑sale modules for design, development, and verification.

A product detail page can be split into base, stimulus, parameters, and supplement modules for competitive analysis and optimization.

HSB color mode can be divided into 3, 6, 12, or 24 segments to modularize color learning.

Conclusion

Simplicity is a process of stripping away the non‑essential to reveal the essence, thereby accelerating information acquisition. Modular design is a key method to achieve simplicity, enabling complex information to be conveyed quickly, completely, and clearly.

Visual design primarily addresses cognitive challenges; modular design improves the speed and quality of cognition. Although the author is not a psychology expert, the principles discussed are grounded in cognitive psychology.

Reference:

Baike.com – Cognitive Psychology

Miller, G. A. (1956). "The Magical Number Seven, Plus or Minus Two"