This is an interesting point of Newtonian physics, because it requires you to look at the world a different way. Our normal experience is that when something is in motion, it only moves for a certain period of time, then it slows down and stops. No matter what it may be, whether a spinning top, a thrown ball, a falling rock, whatever, everything comes to a stop, sooner or later. Newton's insight is that motion does not just evaporate, it doesn't disappear of its own accord, motion stops because something stops it. Things stop moving because there is some kind of friction or other force which opposes that motion. Whereas, when an object is moving in an environment in which there is no force opposing that motion, it will just keep moving. Inertia is that property which allows motion to continue. Inertia does not just dissipate, it remains, until some other force counteracts it. That is why we say that an object in motion will tend to remain in motion. It does have that tendency, even though in our normal experience, other factors are going to overcome that tendency.
The tendency for an object in motion to remain in motion is called inertia of motion.
Newton's first law of motion
...by an unbalanced force
in the presence of balance force the object will tend to remain in constant uniform motion, that means moving in a straight line at a speed that doesn't change including possibly zero
Because the object has inertia. This is codified in Newton's First Law of Motion, that the velocity of an object remains constant unless the object is acted on by an imbalanced force.
The tendency for an object in motion to remain in motion is called inertia of motion.
Newton's first law of motion
An object doesn't "want to" do anything. An object in motion has the natural tendency to remain in motion.
Force
An object at rest tends to remain at rest - an object in motion tends to remain in motion.
...by an unbalanced force
The object will remain at rest if it was at rest or will maintain its motion with uniform velocity if it was moving.
in the presence of balance force the object will tend to remain in constant uniform motion, that means moving in a straight line at a speed that doesn't change including possibly zero
If all forces of an object are balanced, then the motion of the object will remain the same. For instance, if all forces are balanced and if the object is moving, then it will continue to move. If it's still, it will remain still.
Because the object has inertia. This is codified in Newton's First Law of Motion, that the velocity of an object remains constant unless the object is acted on by an imbalanced force.
An object at rest will tend to stay at rest and an object in motion will tend to stay in motion until an exterbal force acts on it is called INERTIA.
Friction and/or Gravity