-- Why did the pedestrians cross the road? Before they got to the other side, they likely pressed crosswalk buttons. But in Dallas and New York City, walkers who pushed the metal buttons likely pushed placebos that did nothing to influence traffic patterns.
Only about 9 percent of crosswalk buttons in New York actually work, a New York City Department of Transportation spokeswoman told ABC News.
"The majority of traffic signals in New York are programmed with a fixed-time operation so the 'walk' message is displayed automatically during each phase of the signal cycle," the spokeswoman said. "Citywide, there are about 100 active push-to-cross pedestrian buttons."
Those 100 active buttons are referred to as "actuated" pedestrian signals, she said.
"At intersections where buttons are no longer functional, the 'walk' message still gets displayed since the signal operates on a regular interval," she said.
New York City's Department of Transportation estimated there were about 1,000 intersections with "decommissioned buttons."
"These are removed when capital projects are scheduled for locations that include them or these intersections undergo other modifications," the spokeswoman said.
In Dallas, nearly all of the 200 traffic signals operate on a pre-timed basis, so hitting crosswalk buttons do nothing, the Dallas Morning News reported on Wednesday.
The ineffective or decommissioned buttons weren't a surprise to an engineer for a crosswalk button manufacturer.
Zane Sapp, senior engineer from Campbell Company in Idaho, which sells the buttons to the cities through a distributor, said it's up to cities to connect the buttons to the traffic signals.
Campbell Company manufactures all sorts of crosswalk buttons in the U.S. Some are marketed as audible buttons to inform the blind of the waiting time to cross the street.
“I would guess the majority of Americans don’t know how traffic signals work," he told ABC News.
He suggested cities educate residents and visitors to improve the efficiency of transportation and movement.
In those intersections where crosswalk buttons do influence traffic, he said pushing multiple buttons to cross a street in different directions can slow drivers and pedestrians alike.
Cities can provide technology enhancements for impatient walkers, he said, including new buttons that provide an audio or visual confirmation such as a light that the press was registered.
He said, "People like to press buttons 20 times."