I’m leading a workshop in a fancy business building in Lisbon this week, and they have a very interesting elevator system. There are no buttons inside the elevator, but instead a touchscreen outside, where you indicate which floor you want to go to.
And it’s an unmitigated User Experience disaster. I have a master in operations research from way back, and I recognize that fitting people into elevators is an instance of the bin packing problem (literally ;-). With information about everyone’s destination, you can produce an optimal allocation of people to elevators.
But look at the screen above. If I’m on the seventh floor, where do you think I want to go? In 95% of the cases to the ground floor. How do I get there? By pressing the small triangle at the bottom and scolling down to find the ground floor.
This is why engineers should never be allowed to design user interfaces.