what would happen if someone damaged his cerebellum
Damage to the cerebellum can result in dizziness, vertigo, ataxia which is an inability to coordinate voluntary muscle movements, unsteady movements and staggering gait. This can interfere with a person's ability to walk, talk, eat, and to perform other self care tasks. Other symptoms of a damaged cerebellum include poor motor control, the overestimation or underestimation of force, the inability to engage in rapidly alternating movements, loss of balance and loss of muscle memory.
As cerebellum is required to maintain your muscle coordination and equilibrium, any damages to your cerebellum might lead to the disturbances in your muscle coordinate and balance, (BUT, without muslce paralysis). Some of the clinical manifestations that you might have: motor (cerebellar) ataxia; tremor during movemnts (disappear at rest)