on corners, its easier to get the vehicle to slide because both tires will spin.
with an open differrencial, the outside tire just rolls along and keeps the vehicle from sliding while the inside tire spins.

With open differrncial, you get a skid steer type turn like a bulldozer. one side does nothing while the other sidee spins you around in a circle. with a locker or lsd, the force is more balanced.