WCAG (Level AA) SC 3.3.4 Error Prevention (Legal, Financial, Data) (w3.org)
Issue description
WCAG 3.3.4, “Error Prevention (Legal, Financial, Data)” focuses on helping users avoid serious consequences when submitting forms that involve legal commitments, financial transactions, or data updates. It recognizes that errors in these types of forms can have significant repercussions, and providing mechanisms to prevent or mitigate those errors is crucial for accessibility.
Many websites that handle legal, financial, or data-related forms don’t provide adequate error prevention mechanisms. This can lead to:
- Legal complications: Users might accidentally agree to terms or submit legally binding information without fully understanding the consequences.
- Financial loss: Users might make errors in financial transactions, leading to unintended payments or losses.
- Data loss or corruption: Users might submit incorrect or incomplete data, leading to data loss or corruption.
- Frustration and stress: Making irreversible errors can be highly frustrating and stressful for users.
WCAG requirements
This guideline requires that 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:
- Reversibility: Submissions are reversible.
- Checked for input errors: Data entered by the user is checked for input errors and the user is provided an opportunity to correct them.
- Confirmed by the user: A mechanism is available for reviewing, confirming, and correcting information before finalizing the submission.
Benefits
- Reduced errors: Error prevention mechanisms help users avoid making costly or irreversible mistakes.
- Improved user confidence: Users can feel more confident when submitting important information, knowing that there are safeguards in place.
- Enhanced accessibility: It makes forms more accessible to users with cognitive disabilities who might be more prone to errors.
Essentially, this guideline promotes responsible design by encouraging websites to implement mechanisms that help users avoid serious consequences when submitting forms that involve legal, financial, or data-related information.
Related requirements
The following WCAG source criteria are often related to this as well. They can provide additional insights into specific challenges you may be encountering.
Who this issue impacts
Follow the links for additional information on user impairments:
Suggestions for remediation
Remediating WCAG 3.3.4 “Error Prevention (Legal, Financial, Data)” involves implementing mechanisms to help users avoid and correct errors in forms that handle sensitive information, such as legal commitments, financial transactions, or data updates. Here’s how:
Reversibility
- Undo functionality: Provide a way for users to undo or reverse submissions, especially for actions with significant consequences (e.g., placing an order, making a payment, deleting data).
- Confirmation pages: Use confirmation pages that allow users to review and confirm their submission before it is finalized.
- Reversible actions: Design the system so that actions can be reversed if necessary (e.g., allow users to cancel orders or restore deleted data).
Error checking
- Input validation: Implement robust input validation to check for errors in real-time as the user enters data.
- Clear error messages: Provide clear and specific error messages that explain the error and how to correct it.
- Highlight errors: Visually highlight fields with errors to draw the user’s attention.
Confirmation mechanisms
- Review and confirmation: Provide a mechanism for users to review and confirm the information before submitting the form. This could be a summary page or a confirmation dialog.
- “Are you sure?” prompts: For critical actions, use “Are you sure?” prompts to confirm the user’s intent before proceeding.
- Clear calls to action: Use clear and unambiguous calls to action (e.g., “Submit Order,” “Confirm Payment”) to avoid accidental submissions.
Testing
- Test different scenarios: Test the form with various input errors and scenarios to ensure that the error prevention mechanisms are effective.
- Assistive technology testing: Test with screen readers to ensure that error messages and confirmation prompts are conveyed correctly to users.
- User testing: Conduct user testing with people with cognitive disabilities to get feedback on the usability and effectiveness of the error prevention mechanisms.
Examples
- Online banking: Before processing a payment, display a confirmation page with the transaction details and require the user to enter a confirmation code.
- E-commerce checkout: Provide a summary page with the order details and shipping information before finalizing the purchase.
- Account deletion: Require users to enter their password or answer a security question before deleting their account.
By implementing these techniques, you can help users avoid costly or irreversible errors, improve user confidence, and make your website more accessible to everyone, especially those who may be more prone to errors due to cognitive disabilities.
