Because it remembers where you were when you turned it off and what direction you were travelling in. So it remembers you driving into the drive and as there's no road out the other end, it'll tell you to turn around.
Good question! what if I've driven somewhere else without using the Stuttering Tom? Does it know which way I'm facing when I switch him on again? I've never thought about that before now! LOL
Good god, do you really need a sat nav to tell you which way your car is facing in the driveway? Technology eh?! Where would we be without it.
"reverse out of driveway and turn left" Really? I was planning on ploughing straight through the garage, down the garden and driving through my neighbour's lounge!