n. A device or object that appears to perform a specific function, but in fact does nothing at all.
Consequently, most of the devices were deactivated by the later 1980s, but the buttons themselves and the signs bearing the instructions for their use remained in place. Evidently there was never any official announcement about the status of the "mechanical placebos."
And surely the mechanical placebo of all times has to be the "Complaints"/"Suggestions" box?
The city deactivated most of the pedestrian buttons long ago with the emergence of computer-controlled traffic signals, even as an unwitting public continued to push on, according to city Department of Transportation officials. More than 2,500 of the 3,250 walk buttons that still exist function essentially as mechanical placebos, city figures show. Any benefit from them is only imagined.