The process of manufacturing men's fragrances is a highly complex procedure. Even if the ingredients of a certain fragrance were to be made public (highly unlikely as they are a closely guarded secret) it would be next to impossible for the layman to produce the same fragrance. Thus the reason its a multi-billion dollar industry.

Why else would such big named fashion designers get involved in the production of men's fragrances? And not only fashion designers either. There are actors and actresses, super models and even movie production are becoming involved in making and selling their own designer perfume range. Take Twilight the Perfume for example - based on Twilight the movie and Stephenie Meyer books. Its big big business for all those involved in it!