--- name: develop-design-rationale description: Documents the reasoning behind design decisions including alternatives considered, trade-offs evaluated, and principles applied. Use when making significant UX decisions, aligning with stakeholders on design direction, or preserving design context for future reference. phase: develop version: "2.0.0" updated: 2026-01-26 license: Apache-2.0 metadata: category: specification frameworks: [triple-diamond, lean-startup, design-thinking] author: product-on-purpose --- # Design Rationale A design rationale document captures the "why" behind design decisions—the context, constraints, alternatives considered, and reasoning that led to a particular solution. While designs themselves show what was built, rationale documents preserve institutional knowledge about why it was built that way. ## When to Use - When making significant UX decisions that affect user experience - Before design reviews to prepare stakeholder discussions - When multiple valid approaches exist and the choice needs justification - To onboard new team members to existing design decisions - When revisiting past decisions to understand original reasoning - During design system evolution to document pattern choices ## Instructions When asked to document design rationale, follow these steps: 1. **State the Decision** Begin with a clear, one-sentence summary of what design decision was made. This becomes the title and reference point for the document. 2. **Describe the Context** Explain the situation that prompted this decision. What problem were you solving? What constraints existed? What user needs informed the direction? Include relevant research findings. 3. **List Options Considered** Document at least 2-3 alternatives that were evaluated. For each option, describe what it would look like and its key characteristics. Be fair to all options—avoid strawmen. 4. **Define Evaluation Criteria** Specify how options were assessed: usability heuristics, technical feasibility, brand alignment, user research findings, business requirements, or design principles. 5. **Explain the Reasoning** Walk through why the chosen option best meets the criteria. Be explicit about trade-offs—what you gained and what you sacrificed. Acknowledge where the decision is reversible vs. irreversible. 6. **Document Trade-offs Accepted** Every design decision involves trade-offs. Name what you gave up and why it was acceptable. This honesty helps future teams understand constraints. 7. **Note Follow-up Considerations** Capture anything that needs attention later: metrics to watch, conditions that might warrant revisiting the decision, or related decisions to make. ## Output Format Use the template in `references/TEMPLATE.md` to structure the output. ## Quality Checklist Before finalizing, verify: - [ ] Decision is clearly stated in one sentence - [ ] Context explains the "why now" and constraints - [ ] Multiple alternatives are documented fairly - [ ] Evaluation criteria are explicit - [ ] Reasoning addresses why chosen option beats alternatives - [ ] Trade-offs are honestly acknowledged - [ ] Document is useful to someone inheriting this design ## Examples See `references/EXAMPLE.md` for a completed example.