Frontend teams have become pretty good at monitoring what happens after an application reaches production. We track JavaScript errors, API failures, latency and Core Web Vitals. When something changes after a release, these signals help us determine whether the application is healthy.
But there is one gap I think frontend teams often overlook. An application can look completely healthy in those dashboards while an important workflow is unusable for someone navigating with a keyboard or assistive technology.
Imagine a checkout flow where a recent UI change makes the final button unreachable by keyboard. The page still loads. The API responds successfully. There are no new JavaScript exceptions, and performance metrics look normal. Every traditional signal says the application is working, yet some users can no longer complete the purchase.
