One day while manoeuvring, when the engine revs just a little bit more than you expect and you can't get your right foot up off the accelerator and down onto the brake, or if you miss the brake and catch the accelerator with your right foot instead, you will at least damage the car and at worst kill someone. Sadly, when this happens, the driver usually kills someone very dear to him or her. Just bear that in mind. (Co-ordinated drivers brake with either their right foot or their left foot whether driving manuals or automatics, depending on what they want the car to do, but that requires more skill than simply left foot braking an automatic in a manoeuvring situation.) Full explanation at: www.honestjohn.co.uk/faq/driving-automatics-safely