intermediate

WCAG basics

Explain WCAG principles, success criteria, audit evidence, and practical remediation without treating checklists as the whole user experience.

WCAG (Web Content Accessibility Guidelines) organizes accessibility around **POUR**: Perceivable, Operable, Understandable, Robust. Levels **A**, **AA** (common legal/product target), and **AAA** increase requirements. Success criteria are testable statements—not a substitute for usability testing with disabled users.

| Principle | Interview hook | |-----------|----------------| | Perceivable | Text alternatives, contrast, captions | | Operable | Keyboard, enough time, no seizures | | Understandable | Predictable UI, readable language, error help | | Robust | Valid semantics, compatibility with AT |

					Audit stack:
1. Automated scan (axe, Lighthouse)
2. Keyboard walkthrough
3. Screen reader smoke on critical paths
4. Manual contrast and zoom at 200%

Compliance evidence combines tooling, manual tests, and defect tracking with severity—not a single green Lighthouse badge.

On interviews: AA vs AAA trade-offs; difference between WCAG and Section 508; how to prioritize remediation backlog; VPAT role in procurement.

Common pitfalls: treating automated pass as done; fixing only homepage; ignoring mobile AT; checklist culture without user feedback.

The trade-off is legal/checklist coverage versus lived experience of assistive technology users.

Checklist:

Target AA for customer-facing flows unless policy says otherwise.
Document known exceptions with plan and owner.
Re-audit after major redesigns.
Include disabled users or specialists in validation when possible.