While it's generally a good idea to make your app/site accessible to all users and user agents - the trouble usually comes when you're big enough to get sued.

While it's generally a good idea to make your app/site accessible to all users and user agents - the trouble usually comes when you're big enough to get sued. In my previous life at an ad agency we had a number of clients getting pursued by accessibility lawyers and firms. These were typically nothing more than shakedowns for some insignificant settlement (<$10k) - but it was an open-and-shut case if you wanted to take it to court so it was just easier to settle and spend a couple of sprints on WCAG best practices. IANAL and my agency didn't do the actual implementation so it was typically up to the client to sort out - but having a lawyer on hand should be one of the first things you take care of once you start making or accepting large amounts of money.