What kind of people usually object to travelling by sea?

People usually object to traveling by sea because of the health reasons. It is well-known that the extended stay in the closed environment may cause severe attacks of paranoia to those unaccustomed to such type of staying. Also, some people may experience a headache or stomach aid because of the rhythm of waves that may cause people to throw up or feel pain. Finally, traveling by sea may be dangerous if not following the safety guidelines, such as always having a contact information with you and being careful on the board.