An objects motion changes

isn't that kinetic energy

only when a nonzero net force is applied to the object.

Explanation:

A net force is the sum of the unbalanced forces acting on an object. An object's motion changes only when a nonzero net force is applied to the object. When a nonzero net force is applied to an object, the object's speed and/or direction changes.

If the forces acting on the object are balanced, they will cancel each other out and will not cause the motion of the object to change.