We don’t want to invalidate the input if the user removes all text. They may need a moment to think, but the invalidated state sets off an unnecessary alarm.

Triggers error messages to render after a field is touched, and blurred (focused out of), this is useful for text fields which might start out erronous but end up valid in the end (i.e. email, or zipcode). In these cases you don't want to rush to show the user a validation error message when they haven't had a chance to finish their entry.

Triggers error messages to show up as soon as a value of a field changes. Useful for when the user needs instant feedback from the form validation (i.e. password creation rules, non-text based inputs like select, or switches etc.)