Because of this myth:
If you do something great [in digital media], people will find it. Quite simply, that never was true. Until you can drive traffic to your social media effort, you've got a tree falling in the forest, heard only by those standing nearby. A great number of tools can drive traffic, including StumbleUpon, Digg, and Twitter, but nothing works better than word of mouse—one friend telling another, "Hey look at this!"
And what, other than sheer viral momentum, creates the word-of-mouth spark in the first place?
Could it be….Radio?
That old-fashioned medium that does nothing better than reach lots of people at the same time with one clear message.
Everything old is new again.