Inertia is the resistance to change in motion so inertia depends solely on what?

Inertia is the natural state or tendency of object/s to resist changes in their current status of motion. Naturally, objectsf have a great tendency of keep doing whatever they are doing. The ability of the object to resist change in motion absolutely depends on its mass. The greater the mass of an object has the greater its tendency to resist change when it is in motion. Similarly, the lesser the mass of an object, the lesser is its capacity to resist change when it is in motion because inertia is directly dependent on its mass.