Because the host discovered it was futile to keep talking with the guest.
Explanation:
This is a very common behavior after the subject identifies a strong limitation between dialogue. It points out ignorance or the lack of ability to observe a phenomenom from a different perspective. Therefore it is very difficult to create a debate without any bias between both. It is frustrating because the person unable to analyze the phenomenom from another perspective will die to let you know that he or she is correct. But it is because of his or her inability to see the event far away from his or her centered point of view.
