No single device has done so little good and caused so much annoyance as the car alarm. Before we turn to just how ineffective that blaring bit of ersatz security is (and how effective other forms of anti-theft devices are), let's examine first how this invention went awry.
https://www.popularmechanics.com/cars/a17477/why-the-hell-do-they-still-make-car-alarms/
https://www.popularmechanics.com/cars/a17477/why-the-hell-do-they-still-make-car-alarms/