One of the areas that one should investigate is the comfortableness of the vehicles. People, of course, would like to use their own cars. Because, they are more comfortable than the public transportation vehicles. People feel more comfortable because there are not any people apart from themselves. They can listen to the radio according to their wish. They do not worry about whether they are standing or sitting. They can make telephone calls in their own cars. They don’t have to wait or catch the buses. When we consider this situation from this aspect, private cars are chosen for transportation.