When designing form validation, you need to prioritize the user's experience. There are several common UX mistakes that can frustrate users and make forms harder to complete. One frequent issue is providing vague error messages, such as simply saying Invalid input without explaining what is wrong or how to fix it. Another mistake is blocking form submission without giving any clear reason, leaving users confused about what needs to be changed. Clearing all user input after an error is also a major problem, as it forces users to re-enter information that may have already been correct, increasing frustration and the likelihood of abandonment.

To create a better experience, always make sure error messages are specific and actionable. Instead of saying Invalid password, say Password must be at least 8 characters. Avoid erasing user input after validation errors; keep the data so users only need to correct the problematic fields. Provide feedback that is easy to notice but not disruptive—use inline messages or subtle highlights rather than alert boxes that interrupt the flow. Show errors as soon as possible, but avoid overwhelming the user with messages before they have finished typing. These tips help users complete forms more efficiently and with less frustration.