principle-exhaust-the-design-spacelisted

# Exhaust the Design Space When a novel interaction or architectural decision has no established precedent, explore several concrete alternatives before implementation. Building the wrong thing costs more than exploring three options. **The rule.** When the right answer is not obvious, build 2-3 competing prototypes or sketches. Compare them side by side. Only then commit. Design it twice is this rule by another name. - Alternatives must differ in the dimension under question: structure, interaction model, or tradeoff. A second flavor of the first shape does not count, and neither does the same shape restyled. - Prototypes answer the question; they do not ship. Divergence is cheap only while the alternatives carry no production obligations. - Keep the studies and record the pick with a short "chose B because" note. That pair is the decision's record (the **record-decisions** principle skill). **When it applies:** - Novel UI interactions (no prior art in the codebase) - Architectural choices with multiple viable approaches - Product design decisions where user experience depends on feel, not logic **When it doesn't:** - Mechanical implementation where the pattern is established - Bug fixes or refactors with a clear target state - Changes where constraints dictate a single viable approach