Creative Blindness by Dave Trott
The buttons on traffic lights do nothing between 7am and midnight beyond displaying 'WAIT' (in central London and other towns around the country). The button is a 'placebo', a 'benevolent deception' to give the 'illusion of control' and make people be more patient.
I must admit I was completely 'blind' to that. Highly recommend this book. A few other things that have stayed front of mind...
* The NRA spent around $30m getting Trump elected. But under Trump (unlike Obama) the future of guns became secure, so people no longer rushed to buy them (profits of America's oldest gun manufacturer fell 90%) - that's the scarcity effect! *
* Removing fly posters is expensive (250k a year for one council) so a council in the East Midlands instead paid a local printer £240 to print 1,200 bright orange strips saying 'CANCELLED' and slapped them over the posters. The effect was immediate because the council switched from thinking "We don't want these posters up" to "What can we do to make the offenders think they don't want these posters up" *
* In 1774 Prussia, peasants wouldn't grow potatoes (didn't want them) so, the king banned peasants from eating potatoes and placed guards around the Royal potato patch. Soon everyone wanted potatoes and they became a staple food all over Prussia.