When you elect someone who has no problems embarrassing himself and no problems lying, and in fact likes doing those things due to temporal expediency. Why do you expect him to hire people who do the opposite?

First many people who have vastly different temperament would not want to be said president's spokesman. If you value the truth and take pride in being honest why would you want to be a mouthpiece for a person who constantly lies (see things like crowd sizes, wiretapping, etc)

Second the president would not value this different temperament in hiring you in the first place, being in his good graces while he keeps you, and remembering your honesty when he decides not to fire you for he is not happy with you.

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Now lying and not being an embarrassment, is not the same thing as BEING DAMN STUPID, but there seems to be some form of correlation. I am not saying there is some form of causation here, but stupid people seem to hang out with people who have no ethics or moral compunctions.