Anyone that owns a business knows a difference between profit and loss ... Than explain to me why would someone spent millions of dollars to get a job that pays only $200,000 a year? That's a shitty investment either way you slice it.
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As in many other jobs, Presidents's total compensation far exceeds base salary, especially if you include speaker fees, book royalties and other perks, which ex-presidents get to keep for life.
That being said, most candidates seek presidency not for money, but to advance a point of view and leave historical legacy, which is priceless.