1) mountain driving with the older gearboxes that don't have a manual shifting option. Sometimes the auto up or downshifts at inappropriate times, particularly on a downgrade.

2) When buying any older used car one usually doesn't know how badly the previous driver might or might not have abused the trans on that specific car. Everytime I see a neighbor rocking his auto trans car when stuck in snow instead of shoveling a bit, I make a mental note not to buy his car.