It is worth remembering that there is a difference between being successful and becoming successful and hence there are different drivers.
To remain successful takes discipline, constant innovation, consistency, sensitivity to change etc.
To become successful, however, you first have to overcome the hurdle of making people aware of your existence (as a store/brand).
The best, cheapest, fastest and most effective way of doing this is to be different.
Lady GaGa is a phenomenal lesson in creating attention.
Not much of a looker, but everybody is watching.
Not much of a singer, but everyone is listening.
And it only comes down to this one thing: she is different in a world of clones and copycats. And more importantly, she is different in an interesting way.
The challenge for her (and brands who want to follow her path) is to be different, be different in an interesting way – and then, to become a long term success, be different and interesting and relevant.
That reminds me a bit of the Apple approach, no?