Stability and safety
Look around you and see how many objects could topple over.
Bottles,table lamps ad floor-standing bookcases are just a few objects which can topple over easily. Lots of objects are designed for stability so they can't topple easily.
Look at a tractor on a hillside. It doesn't topple because the line of action acts within its wheelbase.
If the line of action goes outside the wheel base it will then topple.