Does the elevator "Close Door" button really do anything?

From underscorebleach.net I found this:

Probably the best summary of explanations for the "close button issue" is this:

Having consulted with various elevator repairmen, I would say that apparent CDB [close door button] nonfunctionality may be explained by one of the following:

• The button really does work, it's just set on time delay.

  Suppose the elevator is set so that the doors close automatically after five seconds. The close-door button can be set to close the doors after two or three seconds. The button may be operating properly when you push it, but because there's still a delay, you don't realize it.

• The button is broken. Since a broken close-door button will not render the elevator inoperable and thus does not necessitate an emergency service call, it may remain unrepaired for weeks.
• The button has been disconnected, usually because the building owner received too many complaints from passengers who had somebody slam the doors on them.
• The button was never wired up in the first place. One repair type alleges that this accounts for the majority of cases. In other words, the whole thing is a total scam. Watergate, Iran-contra, and now this. And they wonder why we've lost faith.

The site also has these interesting things:

• How to "hack" an elevator—force it to go directly to your floor without making any stops
• How to "hack" a crosswalk button—force it to change from "don't walk" to "walk" immediately (and the traffic light, too, thankfully)

Link

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