Why Accessibility Testing Requires More Than Just Automated Tools

Just because a website passes some accessibility tests doesn’t mean it’s accessible. Many organizations start with good intentions, running checks with tools like Google Lighthouse or WAVE by WebAIM, but there’s a big gap between these automated scans and true accessibility. Accessibility is more than just code; it’s about the people who use the website—especially those with disabilities.

The Limitations of Free Accessibility Tools

Automated tools like Google Lighthouse and WAVE can be a great starting point for identifying potential accessibility issues. They’re convenient, cost-effective, and quick, offering insights into color contrast and missing alt text. However, these tools have their limits:

Partial Coverage: Automated tools can only check for about 20–30% of accessibility requirements outlined in the Web Content Access Guidelines (WCAG). This is because many accessibility issues require human interpretation, such as evaluating the clarity of link text or the logical order of content.

False Positives and Negatives: Automated tests sometimes flag issues that aren’t actually problems or, worse, miss critical issues altogether. For example, these tools can confirm whether an image has an alt attribute but can’t assess whether the description is meaningful.

No Substitute for Human Insight: Accessibility goes beyond code and includes user experience, which is challenging for algorithms to evaluate. Consider keyboard navigation: automated tools can’t fully simulate how a keyboard user moves through a page or interacts with elements.

The Problems with Accessibility Plugins and Overlays

In recent years, accessibility overlays and AI plugins have become popular as a “quick fix” for accessibility. These solutions promise to make sites accessible with minimal effort. However, the reality is more complicated. Often, these plugins make sites harder to use for people with disabilities.

Adding Complexity: Many overlays introduce additional layers of code that disrupt screen readers and interfere with assistive technology.

False Sense of Security: Overlays give the appearance of compliance but don’t address the underlying issues. Websites using overlays might pass certain automated checks but fail manual testing and real-world use.

Making Problems Worse: In documented cases, overlays have introduced new accessibility issues, such as hiding content from screen readers or creating keyboard traps.

Building an Effective Accessibility Testing Process

Accessibility requires a comprehensive testing process that combines automated and manual testing. This process includes several key steps:

Automated Testing: Automated tools are useful for catching low-hanging fruit, like color contrast or missing form labels, but they should be just the first step in the testing process.

Manual Testing: Human testers can catch issues that tools miss. For example, they can check whether all interactive elements are reachable via keyboard, ensure forms are logical to navigate, and confirm that visual cues (like icons and buttons) are meaningful.

Issue Verification: Once accessibility issues are flagged, they must be tracked and verified as resolved. A crucial part of the accessibility process is ensuring that each fix addresses the issue and doesn’t introduce new problems.

Testing with Disabled Users: True accessibility testing involves real people. By involving users with disabilities, organizations gain insights that no automated or manual test alone can provide. These users bring authentic experiences, highlighting areas where the website’s design may fall short of real-world accessibility needs.

Accessibility Governance: Making Accessibility a Continuous Process

Accessibility isn’t a one-and-done project—it’s an ongoing commitment. A governance process ensures that accessibility is considered at every website development stage, from design to deployment. In a well-structured accessibility governance model:

Testing Is Continuous: Accessibility checks happen during design, development, and after updates. This ensures new content or features don’t introduce new barriers.

Cross-Functional Teams: Accessibility governance involves a range of roles—from developers and designers to content creators and QA testers. Each team member plays a role in keeping the website accessible.

User Feedback: Regularly collecting feedback from users with disabilities ensures that the site remains accessible and meets real user needs. This feedback loop is essential for continuous improvement.

Conclusion: Moving Beyond “Good Enough” Accessibility

Automated tools and plugins can play a role in accessibility testing, but they can’t replace a comprehensive approach led by digital accessibility experts. An effective accessibility strategy includes multiple types of testing—automated, manual, and real-world testing with disabled users. By following a thoughtful, structured process, organizations not only achieve compliance but also provide a truly accessible experience for all users. This commitment is more than just checking boxes; it’s about making the web more inclusive and usable for everyone.

To get your accessibility questions answered privately and take the first step toward professionally correcting your website's accessibility issues, contact us at Inclusive Web Our team is here to support your journey toward a more inclusive digital experience.