Contents
What convergence means
| Input | What to extract |
|---|---|
| Interface audit | Repeated patterns, inconsistencies, missing states, one-off solutions. |
| Product roadmap | Where the system needs to support scale, new flows, or new teams. |
| Research and support data | Where users get confused, blocked, or forced to ask for help. |
| Engineering constraints | What can be maintained in code and what creates rework. |
| Brand direction | Which parts of expression should be fixed, flexible, or avoided. |
How to write useful principles
| Weak principle | Usable principle |
|---|---|
| Be simple. | Show the next required action before optional detail. |
| Be consistent. | Reuse a pattern when the user goal, risk, and data shape are the same. |
| Be flexible. | Allow local variation only when the product context changes the user need. |
| Be accessible. | Accessibility requirements are baseline acceptance criteria, not final QA notes. |
| Be on brand. | Use brand expression to clarify priority or state, not to decorate every surface. |
How to measure principles
| Principle area | Signal to watch |
|---|---|
| Clarity | Task success, reduced support questions, fewer repeated explanation patterns. |
| Consistency | Pattern reuse, fewer duplicate components, fewer UI QA issues. |
| Accessibility | WCAG issues, keyboard flow, focus states, error recovery, target sizes. |
| Speed | Reduced design rework, faster handoff, fewer engineering clarification loops. |
| Governance | Contribution acceptance rate, review cadence, documented exceptions. |
Who owns the system
| Model | Works when | Risk |
|---|---|---|
| Single owner | The product is small and the system is still early. | The system depends too much on one person. |
| Central team | Many product teams need shared components and quality control. | The team becomes a service desk instead of a system owner. |
| Federated model | Multiple teams need ownership and contribution rights. | Governance can get slow without clear rules. |
| Open contribution | The system is mature and contribution standards are documented. | Quality drops if review is weak. |
