There are people who are so out of touch with technology that they might not understand the (to us, incredibly obvious and clear) feedback the UI is providing, and might overlook it or be scared of pressing the screen again. Grandmothers and curmudgeons.
It seems ridiculous to be unable to comprehend something that would be as familiar as using a hand calculator to people like me and you, but there are people out there who are afraid to touch the power button on their computers because they think they'll burn their house down or get a virus or something.
Imagine people like that trying to learn a brand new user interface in the span of 5 minutes while people are waiting in line for them to finish. It's a small population of people but it could conceivably make a difference given the right conditions.
edit: I forgot to add that this would be a good way to commit voter fraud and still have plausible deniability. Also, it would probably be more cost efficient to bribe someone for this small bug that gives a 0.5% advantage than it would be to pay for the campaigning that makes a 0.5% difference.
That's not the point. Yes, there might be people who will ignore the UI feedback and cast the wrong vote. The point is that, if you're going to tamper it, you'd rather tamper the back end. As it is, if this is happening to a lot of people, many of them are bound to report it and that risk completely outweighs any gain from the "grandmother" group.
In any case, I'm skeptical of the tampering hypothesis because only one person reported and filmed it.
It seems ridiculous to be unable to comprehend something that would be as familiar as using a hand calculator to people like me and you, but there are people out there who are afraid to touch the power button on their computers because they think they'll burn their house down or get a virus or something.
Imagine people like that trying to learn a brand new user interface in the span of 5 minutes while people are waiting in line for them to finish. It's a small population of people but it could conceivably make a difference given the right conditions.
edit: I forgot to add that this would be a good way to commit voter fraud and still have plausible deniability. Also, it would probably be more cost efficient to bribe someone for this small bug that gives a 0.5% advantage than it would be to pay for the campaigning that makes a 0.5% difference.