From a Reddit thread on Texas voting machines. This is a pretty egregious failure on the part of some UI developer somewhere, but it does speak to an often overlooked part of UI development: if a user can see an interface, they’re going to try to interact with it, and it’s your job to make sure that they can. If you don’t have a good understand of what interactive means (or what can block it), Phillip Walton’s recent post, “Idle Until Urgent” is a good read.