Do you ever feel that pressing the "close door" button on the elevator doesn't do much to speed things along? As it turns out, there's a big reason for this phenomenon: the buttons don't actually work.

Karen W. Penafiel, executive director of the trade group National Elevator Industry Inc., dropped that bombshell while being interviewed by the New York Times about so-called "placebo buttons." Penafiel says the industry started disabling the "close door" feature after passage of the Americans With Disabilities Act in 1990. The legislation requires all elevators to remain open for a set period of time to allow anyone who uses crutches, a cane or wheelchair to get on board. No amount of button mashing makes any difference.

“The riding public would not be able to make those doors close any faster,” she told the Times.

While "close door" buttons are useless to the general public, they still serve a purpose in specific circumstances. "The button is there for workers and emergency personnel to use, and it only works with a key," David McRaney, author of a book about self-delusion, "You Are Not So Smart," told Yahoo in 2011.

They don't work, but apparently, we need them

McRaney goes on to explain that while placebo buttons are all around us, their continued existence makes us feel good. Another classic example he shares are the walk signal buttons in many towns. In places like New York City, the buttons are for show only — with officials long having moved over to automated lights set to a timer.

"Just as with the elevators, it would be expensive to replace or remove all of the non-functioning buttons or to inform the public through some sort of media campaign," said McRaney. "There is no obvious harm in letting the people in your town keep impotently jamming crosswalk buttons."

In fact, pressing buttons, even dumb ones, offers a level of gratification that, psychologist Ellen Langer told the BBC, makes you feel as if you have control over your world.

“Doing something is better than doing nothing, so people believe,” she said. “And when you go to press the button your attention is on the activity at hand. If I’m just standing at the corner, I may not even see the light change, or I might only catch the last part of the change, in which case I could put myself in danger.”

As for the close door buttons on elevators, you might still get lucky. While most elevators have been updated over the last 25 years to reflect the 1990 Americans With Disabilities Act, there are still a select few with a working "close door" command. So go ahead and keep pushing those buttons. We won't tell anyone.