"The host never admits they are, were, or could be wrong. A guest on, say, Charlie Rose's or Bill Moyers' shows is there to educate the listeners and the host. But a guest on Glenn Beck's or Rush Limbaugh's shows are there either to agree with the host or for the host to browbeat and contradict.
"It's a great business move: If you present yourself as infallible and your listeners believe it, they'll be very loyal listeners, ripe for advertisers.
"Contrast this to a prominent radio host on the left of the spectrum like Amy Goodman of Democracy Now. She shares her point of view through selection bias, inviting guests whose message she wants to spread and letting listeners hear it in a new voice each day. When she has a guest she strongly disagrees with (she hosted Lou Dobbs a few years ago), she sticks to the question format, though with more points and barbs than folks she likes. But she never outright tells a guest their wrong or screams at someone to get off the air."
-flwyd (originally here)