These sources do not carry equal weight
- Standard requirement.
- A testable criterion in a published standard. Whether it is legally required depends on your jurisdiction and contract.
- Government control.
- A control the issuing government expects its agencies and their partners to apply. It does not bind other organisations.
- Design-system convention.
- How one design system does it. Binding only on teams that have adopted that system.
- Research-based best practice.
- Advice drawn from usability research. Persuasive, not mandatory.
- Industry convention.
- A range many shipping products use. Written by Shortcut; no standard or organisation requires it.
- Craft guidance.
- Judgement of the kind given in design review. Written by Shortcut; reasonable designers may disagree.