James Surowiecki, The New Yorker's resident financial columnist, gets to the economic root of the cable news punditry problem, via all those crazy speculations about Malaysia Airlines Flight 370:

... this welter of improbable hypotheses highlights the peculiar economic incentives of punditry. When uncertainty abounds, pundits strive to differentiate themselves from their peers. There's little to be gained from saying what everyone else is saying or, God forbid, suggesting that there isn't enough information on which to base a judgment. Conversely, there can be huge rewards in taking a flyer on an extreme prognosis and turning out to be right. As one recent study of the economics of forecasting put it, "Being the single winner always entails more glory than sharing the prize."

This wouldn't be the case if pundits suffered when their predictions proved wrong. There are forecasting professions where this happens: stock analysts who err are more likely to get fired. But in the media mistaken conjectures tend to be quickly forgotten, so there's little downside to being bold and wrong. This tendency is exacerbated by the demands of cable news. A couple of weeks ago, James (Spider) Marks, a retired general who is a CNN commentator, suggested that, rather than engage in "a cacophony of conjecture" about the plane, people in the studio should "get back to what we know and what we don't know." "You know how cable news works, don't you, Spider?" the host, Bill Weir, said, with a laugh. "We got time to fill here."