Everyone agrees that it is a good idea to track various KPIs for quality. But how do we "grade" accessibility? Fundamentally, accessibility is about usability for people with disabilities, and this is already hard to get a handle on. But there are things that we can measure, track, and grade such as: tests passing vs. tests failing, severity of user impact, and volume of errors. But how does that truly relate to the human experience? Given that 20% of the population has some sort of disability, this is an important topic to nail down. During this talk, I will discuss how I've arrived at the "One True Metric"