Why does only one side of the car have a mirror that says "objects may be closer than they appear"

Many cars have a mirror on the passenger side that is curved to provide a wide angle view. This is so that the driver can see a car in the blind spot (which is worse on the passenger side of the car). The downside of this mirror is that it gives the impression that objects are farther away than they really are. It is decided that the danger of not seeing a car in the blind spot outweighs the danger of mistaking the distance of the car. Most people can learn to adjust to the distorted distance perception anyway. However, on the driver's side, it is more important to provide an undistorted view, so a standard flat mirror is used.