Imagine you're running for president. Of the United States of America. The campaign has begun. Then something unsettling happens: you realize that you're not qualified for the job.
That you're in way over your head becomes evident when voters and reporters on the campaign trail ask you questions you can't answer. What's your position on net neutrality? You don't even know what that means, much less have an opinion about it. What would you, as president, do about the Middle East? You don't have a clue.
If you're like me, you'd probably call the whole thing off. If you give two s—— about your country, you don't want anyone less than the best and the brightest in charge of those awesome powers over war and peace, the world economy and those nuclear launch codes. If and when you come to the conclusion that you are neither the best nor the brightest, or even very good or much brighter than a 60-watt bulb, the right thing to do is to step aside and leave the leading to someone else — someone better, someone brighter.