The problem is targeting a specific audience. Remember when you could scan through the FM dial and know what station it was without looking at the dial? If you heard Debbie Deb, Irene Cara, Cover Girls, TKA, Shannon etc... you knew you were on Hot 103.5, if you were hearing George Michaels, The Bangles, New Kids On The Block you knew you were on Z-100, if you would hear De la Soul, LL Cool J, Gladys Knight, etc... you were on 98.7 Kiss FM, When you heard Culture Club, Men At Work, Elvis Costello, Fock Of Seguls, etc... it had to be WPLJ (prior to "power 95").
Targeting "Demo's" has Sean Kingston on Z-100, WPLJ, KTU, Lite FM etc... Station's no longer have Identities,

What ever happened to Station just identifying themselves by the type of records they would play rather than the "demo" they are after.