Eye
Muscle Imbalance

When the eyes are misaligned, the eye muscles pull the eyeballs in position to prevent seeing double.
Eventually both
the arms holding the steering wheel and the eye muscles pulling the eyeballs
become tired and strained from compensating for their respective errors.
Constant straining of the eye muscles during sustained vision
tasks can lead to ocular tendonitis
Eye muscle imbalances usually vary in different directions of gaze. Some people have eye muscle imbalances that make it difficult to look up while others may not like looking down. Some prefer viewing to the right and other to the left.