Sui generis—one of a kind, the one that defines the genus.
That's the goal of the best kind of marketing. To be the best in the world, because the world is defined by what you do.
The impossible way to do that is to be unique because you're famous. There's only one Oprah, of course, because the thing she's famous for is being famous. There will never be another. Louis Vuitton is in this category, 50 Shades of Grey is, and so is the next hearthrob teen sensation. There is no substitute because the attraction is that this is the famous one, accept no substitutes.
The smart way to do it is to be unique before you get lucky and become famous. Take a listen to an old Talking Heads record or a house designed by Wright early in his career. They were unique before they were famous. This takes more patience, more guts and a lot more weirdness because the thing you're doing is actually interesting before it (if you're lucky) becomes popular. You might not end up as Oprah, but your uniqueness is yours, and it can pay off long before the masses choose you merely because you're the famous one.