In Paul Ford’s funny and informative guide for people who have been asked to be in the media, he lays out “the most important rule of media”:
Nothing matters, and nothing works. If you’re selling a book, everyone will want you to go on TV to promote the book. That will sell negative ten books. Some stupid tweet will sell 1,600 copies of the book. I mean obviously if Oprah wants to feature you and tells people to get your book, the math changes. Sometimes things do work! But in general nothing matters, and nothing works. You won’t cost yourself your career if you say no.
In my experience, this is (sometimes painfully) very true.
For more of Paul’s wisdom, see: “Why wasn’t I consulted?” and “What to say when you don’t know what to say”