9.21 WCAG 2.2 Success Criterion 3.3.3 - Error Suggestion
When a user makes an error and the solution can be identified automatically, always provide the user with a suggestion to fix the error.
Before Rectification
An error message that is not helpful enough because it does not provide an adequate description of what needs to be corrected.
After Rectification
In contrast, the example above shows a message that provides a good explanation of what needs to be corrected.
WCAG 2.2 Reference:
https://www.w3.org/WAI/WCAG22/Understanding/error-suggestion