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THE DOOR CLOSE BUTTON 

James Gleick

Manufacturers need new technologies because the old technologies of short-range vertical transport seem to provoke humans to raw expressions of impatience. Anger at elevators rises within seconds, experience shows. A good waiting time is in the neighborhood of fifteen seconds. Sometimes around forty seconds, people start to get visibly upset. Antsy is the word Fortune uses (odd how we project our haste onto these steady-paced insects.) Once on board, our antsiness only intensifies as we wait for the door to close. How long? Door dwell, as the engineers call it, tends to be set at two to four seconds. For some, that is a long time. And not just Americans. “If you travel in Asia at all, you will notice that the DOOR CLOSE button in elevators is the one with the paint worn off,” says Kendall. “It gets used more than any other button in the elevator. When they’re in the elevator, they want to go.” Japan has pioneered another feature, called “psychological waiting-time lanterns”: as soon as someone presses a call button, a computer determines which car will reach the floor first and lights the appropriate signal well in advance of its arrival. This gives the illusion of an instantaneous response and, as a side benefit, herds riders for position into quick loading. They enter. Then, finally, as the door starts to close, the sight of a new passenger racing toward the elevator creates a moral test (stab the DOOR OPEN button, or feign obtuseness and look away?) which many riders fail to pass.

                Researchers concluded that human elevator operators were time-wasters in their own way – too polite. “Much of time is lost by slow moving passengers who make no effort to hurry,” said the president of Otis in 1953 […] They know the attendant will wait for them… But the impersonal operatorless elevator starts closing the door after permitting you a reasonable time to enter or leave.” It was not just the elevators that would gain intelligence and efficiency. He added, “People soon learn to move promptly.” And so we have. […]

                The doors must close. Everywhere, transportations engineers are pressing to save tiny increments of time. Managers of New York City’s subway system, not known for its clockwork precision, discovered that conductors were failing to enforce a rule that doors must close within forty-five seconds after they open. The effects cascaded through the system: a minute’s delay for one train would cause backups half the length of Manhattan. To hurry passengers along, they tried installing signs that read “Step aside, speed your ride” and digital clocks relentlessly ticking off the allotted time. Then they tried ordering conductors to drop the word “please” from the “Please stand clear of the closing doors.”

                Although elevators leave the factory with all their functions ready to work, the manufacturers realize that building managers often choose to disable the DOOR CLOSE. Buildings fear trapped limbs and lawsuits. Thus they turn their resident populations into subjects in a Pavlovian experiment in negative feedback. The subjects hunger for something even purer than food: speed. […]            

                How many times will you continue to press a button that does nothing? Do you press elevator call buttons that are already lighted? – despite your suspicion that, once the button has been pressed, no amount of further attention will hasten the car’s arrival? Your suspicion is accurate. The computers could instruct elevators to give preference to floors with many calls. But elevator engineers know better than to provide any greater incentive than already exists for repeated pressing of the button. They remember Pavlov. They know what happens to those dogs.

James Gleick (2000). Faster: The Acceleration of Just About Everything. London: Abacus.