Understanding SC 3.3.4 Error Prevention (Legal, Financial, Data)

3.3.4 Error Prevention (Legal, Financial, Data): For Web pages that cause legal commitments or financial transactions for the user to occur, that modify or delete user-controllable data in data storage systems, or that submit user test responses, at least one of the following is true: (Level AA)

1. Reversible: Submissions are reversible.
2. Checked: Data entered by the user is checked for input errors and the user is provided an opportunity to correct them.
3. Confirmed: A mechanism is available for reviewing, confirming, and correcting.

Users make mistakes while inputting data into forms & as discussed before in 3.3.1 Error Identification & 3.3.3 Error Suggestion help us reduce the incorrect submission of data. But when we are dealing with data related to legal, financial or while sharing sensitive information users need to be provided with an option to verify the data & rectify if there are any mistakes. This is because most of the time once the data is submitted it cannot be retrieved immediately & user might have to get in touch with service provider to rectify it. In case of financial transactions once a transaction takes place there is no way to revert it.

For example, if a flight ticket is purchased fora wrong date, there is a chance to rectify it but it comes with a cost where airlines charge a heavy fees to change the date of journey.

To avoid errors like these, users need to be provided with review information screen where all the information provided by the user is populated & user need to review & confirm the transaction before moving ahead.

Users who Benefit

• Users with Cognitive disabilities who can forget too quickly or in utter confusion that arrises out of distraction can enter wrong data
• Users who use screen readers and who have low vision can accidentally delete data due to confusion or in a hurry to submit the form quickly or delete wrong data due to some misunderstanding of the procedure

Points to Remember

• Make sure proper hints are provided to fill the data in the forms
• Provide a review information screen where user provided information is populated
• Provide a checkbox where user can confirm that they have reviewed all the information and they are ready to submit; enable the submit button only when user checks the checkbox
• Provide confirmation screen or dialogue when users delete any data.

References

Understanding Success Criterion 3.3.4