I'd like to follow up on the email about facts and figures from yesterday with another example.
During World War II, the British Royal Air Force noticed that their bombers kept coming back with bullet holes in the wings, tail and body. Very few bombers returned with holes in their engines or fuel tanks.
So they thought they better reinforce the areas with the most damage. After all, if you make those bullet-proof, fewer planes will be likely to go down.
Statistician Abraham Wald argued against that idea.
The reason they didn't see planes with bullet holes in the engine and fuel tanks were because those planes didn't even make it back. Those were the areas that needed extra armour.
They were only seeing the planes that survived. The ones that got hit in less critical spots. The planes that got shot down were the missing data. They told the real story.
So if you're looking at your customer support desk and find no trace of accessibility issues, it doesn't mean you have no issues or no customers with disabilities.
It might just mean that they're abandoning your product without bothering to even tell you about it.