Why is Newton's first law called law of inertia?

All basic a change of motion all from around.

Why is Newton's first law called law of inertia?

Explanation: there is a natural tendency of objects to keep on doing what they're doing. All objects resist changes in their state of motion and in the absence of an unbalanced force, an object in motion will maintain this state of motion.

Unless a net force is present, the objects motion would never be changed.