Kodak makes different types of films because different types of photographers have varying needs and working habits.
Professional photographers tend to buy large amounts of film at once.
They usually expose and process the film within a relatively short time after purchase. Casual picture-takers usually buy one or two rolls of film at a time. A roll of film may remain in the camera at room temperature for several weeks or even months before processing. As films age, their color balance and other characteristics change slightly. Therefore, Kodak allows for this aging process during manufacture.