Think about this analogy. You have a car with a full tank of gas, a well-tuned engine, good set of tires, quadraphonic CD system, and a sleek, polished exterior. There it sits. This car has incredible potential. However, until a driver sits behind the wheel, puts the key in the ignition, and cranks it up, the car doesn't function.
Interest is an important motivator for a student.
So is a desire to learn. When you link these two things together, you create success. Often success in an endeavor leads to more interest and a greater desire to learn, creating an upward spiral of motivation toward a goal you have established. So be honest with yourself.