Why do some people get motion sickness? It has to do with the individual’s physical condition. Some people may experience dizziness, nausea, vomiting, epigastric discomfort, cold sweat, etc. when they have problems with their balance and vestibular nerve regulation due to the bumps or acceleration/deceleration of the vehicle, which is called motion sickness. 2. The speed of the vehicle is not stable, such as frequent acceleration and deceleration or frequent turning movements, which can easily lead to vestibular stimulation, and the patient will experience motion sickness.