Don't blame the talking heads too much. They are typically chosen for their ability to speak clearly and with enough empathy so you don't turn them off due to boredom or an iresitable urge to choke the crap out of them due to their screeching and or shrill voices. It is also useful if they are attractive enough so you don't have to avert your eyes while the TV is on. (if it is a radio program, the latter is not a requirement) Also remember that a room temperature IQ probably helps them to get through an 8 hour day without committing suicide from constantly repeating the same gibberish written by someone with only a slightly higher IQ.