You go through life trusting that the buttons you push and things you buy do what they are supposed to do.  That is not always the case as this list of 5 things you think work, but actually don't shows.

The Elevator "Close Doors" Button

Let's start with the most obvious example: That pesky "close doors" button on the elevator. It's a fairly well-established fact that on most elevators it's what essentially amounts to a dummy button.

But it's not as if elevator manufacturers are installing an extra button just to give you an illusion of control. Indeed, McRaney says the button can be activated, but only by certain people.

"The close buttons don't close the elevator doors in most elevators built in the United States since the Americans with Disabilities Act," explains McRaney. "The button is there for workers and emergency personnel to use, and it only works with a key."

Sure, they could put a sign on the panel explaining the situation to elevator riders, but as McRaney points out, it's hard to justify the time and money it would take. And besides, we'd probably keep pressing it anyway, convinced that this time it will work.

"HD" TV

We're not suggesting that HD TVs aren't really high-definition, though the various technical terminology might make it hard to determine just how good the picture quality really is. But for some people, simply seeing the "HD" label on the TV is enough to convince them that the picture is better, even if they don't have the proper connection or they're not watching an HD channel. Simply being told that it's an HD picture is enough to convince them that the picture is better, and it isn't until their grandkids come over and show them how to find the HD channels that they realize they'd been deluding themselves.

This isn't just anecdotal, though. Dutch scientists conducted a study in 2009 in which 60 people were shown an identical video clip on identical TVs. However, half of them were told that the clip would be in high-definition, and the scientists even attached an extra-thick cable to the back of the TV to complete the charade. The control group was told to expect a normal DVD image.

Afterwards they were asked to describe the picture quality. You can imagine which group thought it was watching the nicer picture.

Of course, at this point HD TVs are ubiquitous enough that most people know when they're seeing a high-definition picture or not. And as one of the scientists explained to New Scientist magazine, the gap between standard definition and high definition is smaller in Europe than it is in the U.S., so it wouldn't be as effective here.

Still, it's a good reminder that an assurance that something is "high quality" doesn't just make it more likely that you'll buy the product — it may also subtly influence your enjoyment of it.

Walk Signal Buttons

Many cities and towns have buttons at crosswalks that allow a pedestrian to speed up the arrival of a walk signal. And in many places, they do exactly what they promise to do.

But not everywhere.

The City of New York admitted several years ago that most of the "push button, wait for walk signal" buttons were no longer active, having long ago been replaced by automated systems that keep all the lights on a set timer. That makes them placebo buttons just like the close door buttons on an elevator.

"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," explains McRaney. "There is no obvious harm in letting the people in your town keep impotently jamming crosswalk buttons."

And many people will keep pushing away — perhaps a holdover from a time when they remember the buttons working, or perhaps because occasionally they'll get lucky and the light will change right after they push.

Again, in many municipalities these buttons actually do work. In 2008, an investigation by Canada.com found that there weren't any such placebo buttons in Victoria, Canada, though city officials admitted that the buttons varied in effectiveness.

See the rest via things-you-think-work-but-actually-dont-mainst: Personal Finance News from Yahoo! Finance.

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