4.1.2 Name, Role, Value
Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies.
Maximize compatibility with current and future user agents, including assistive technologies.
For all user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; and notification of changes to these items is available to user agents, including assistive technologies.
Note 1: This success criterion is primarily for Web authors who develop or script their own user interface components. For example, standard HTML controls already meet this success criterion when used according to specification.