Flawed Product Feature
Question: "In the product requirements module of the Strategic Product Manager course I had attended there is a slide about the 'Chevrolet Cavalier Anti-jacking Devices'. Could you please expand and provide more information about this example?"
The "Chevrolet Cavalier Anti-jacking Devices" slide in the Procedural Requirements Management™ (PRM) seminar is an example of an originally flawed product feature which was improperly designed due to not specifying the necessary constraints when writing the relevant market requirement.
During the 1980's there were incidents in the USA of perpetrators reaching through a car's window while the vehicle was at a stoplight and yanking out the ignition key. Also emerging were incidents of "car-jacking", the theft of a car that involved the forcible removal of the driver of a car. In order to deal with this transgression, car manufacturers began introducing anti-jacking measures, one of them being automatic central locking of the vehicle's doors (and sometimes also the automatic closure of the car's windows).
The early models of Chevrolet Cavalier included automatic central locking. The feature was that all the car's doors will firmly lock fifteen seconds after the car was started. This feature caused people to inadvertently get locked out of their cars while the engine was running. In less favorable events, children were locked in the car while the engine was running.
To fix this flawed feature a constraint of "Individual piloting the vehicle is in the driver's seat" was add to the market requirement. The result was a new feature in which the automatic central locking was activated only after the car was started, the gear was in "drive", and the vehicle was in motion for over fifteen seconds and moving at a speed of at least twenty miles-per-hour (MPH). When all those conditions were met then it was assumed that indeed an individual piloting the vehicle is in the driver's seat and it is now safe to lock the doors.
However, the feature was still flawed because it allowed the automatic central locking to be activated when a child was driving the car. Therefore, the constraint was amended to "adult individual piloting the vehicle is in the driver's seat" and this altered the design to include a weight sensor in the vehicle's driver's seat. Now the automatic central locking was activated only when an adult was in the driver's seat.
So this was an example of a flawed product feature that improperly designed due to the lack of the necessary constraints when writing the relevant market requirement.