第14页 Section 1: The Problem 2 What's Eating the 30-second Commercial?

According to a Knowledge Networks study released in December 2004, 47 percent of viewers switch channels when watching TV, either because a program has ended or to skip commercial. This is up from 33 percent in 1994. 

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Clutter in each medium (number of ads previewing , listening, reading, or using session) has become white noise, and when combined with all the surrounding so-called intergraded media that agencies are selling you on, things have only gotten worse: it is now gray noise.
Consumers have either built up resistance or have figured out ways to avoid, tune out, or ignore Madison Avenue’s obsession with breaking through its self-created clutter.