> What I tend to see in this demo is how to make a doorknob unintuitive, how to make music player functionality undiscoverable, how to accidentally lock yourself out, how to frustrate a user whose mental model of the sensor is incorrect.
The same could be said about touch technology. And usually is, for the first week someone uses it the first time. My friend, a good sysadmin, was often asking me how am I able to figure out how those Android interfaces work, then the other day he got an iPhone, and he was complaining and complaining... until he stopped, after a week or so.
I think discoverability is a bit overrated. Lots of things around us are bad at it, and people learn by showing to each other how to use the stuff. And as long as stuff behaves predictable, we can quickly grasp the patterns, no matter how nonintuitive or counterintuitive they are.
Or maybe I'm wrong, given how often I have to show people how to do things like setting the timer on the microwave or reconfiguring a VCR or whatever, given that they own it for like half a year and for me it's a first time I see a particular model (or sometimes even entire class of devices) and I don't have (nor have a need for) a manual. I don't know, maybe some people have troubles building mental models based on reasonable expectations about what a machine can do (I observed it strongly in one case). Anyway, I'm surprised by this phenomena, given that I once had to show to a good sysadmin how to set a clock on his microwave, 'cause he couldn't figure it out (and long he tried).