When you turn off the skidding car switch you're turning off the stability program that helps keep the car going straight when the tires want to make it go sideways as the car doesn't have a limited slip diff. Doesn't hurt anything if it's not on but you probably got up the hill safer and straighter than you would have had you switched it off. Mine went on twice yesterday just starting from a standstill on about one inch of snow. In the owner's manual it says to turn it off if you get stuck in snow so you can rock the car out.