What advisory means
Advisory techniques improve accessibility beyond what any rule strictly requires. Many come from AAA-level thinking (more generous spacing, plainer language, extra navigation routes), and others address barriers the rules do not formally measure.
They are not enough on their own to claim a rule is met, and skipping them is never a violation. That is the definition: helpful, encouraged, optional.
Why do optional work?
Because advisory techniques are where good experiences live. A site that chases only the minimum produces pages that technically pass and practically frustrate: compliant contrast with exhausting density, passing forms that are still confusing. The advisory list is W3C's collected advice for closing that gap.
There is also a durability argument: several of today's rules began as yesterday's advisory ideas. Teams that adopt the good advice early rarely scramble when standards move.
In audits
We keep advisory findings clearly separated from required fixes, because mixing them is how audits lose trust. Your report marks what is compliance and what is craft, and we only flag advisory opportunities when they are cheap and high-impact.
Formally, advisory techniques carry little weight: nobody can fairly fault a site for skipping one, and knowing the difference protects your budget in both directions.