Tag
requirement-envelopes
- Feb 17, 2026 Designing for the Tails of an Ability Distribution, Not the Mean Why a design calibrated to an average body or an average user excludes most people, and how percentile bands and requirement envelopes replace the average as a design input. accessibility
- Dec 6, 2024 Permanent, Temporary, and Situational Constraints as a Single Design Axis How the same underlying limitation appears as a permanent impairment, a temporary injury, or a situational condition, and why grouping requirements by function rather than by cause avoids duplicated and conflicting solutions. accessibility