There are some roles (like slider and spinbutton) that have related accessibility events (like increment and decrement) that are not exposed in browser APIs currently. Native equivalents (<input type="range"> and <input type="number"> respectively) have some support (when testing with macOS VoiceOver in Safari, the range accepts increment/decrement events, but number does not), but when using the ARIA pattern, this results in making the request to increment/decrement but no resulting change in behavior (since there's no JavaScript event to listen to in order to add the behavior in).

It would be helpful to add warnings for some of the patterns that result in allowing AT events that cannot be supported currently in browsers.