Being POTUS means that you need to pick a side on some very difficult issues and know that a large segment of the country is going to disagree with you no matter what. If you aren't prepared to take a stand, you aren't up to the job.
Presidents who actually accomplish something, good or bad, are decisive. Reagan was decisive and won the Cold War. LBJ was decisive with the Great Society, it has been destroying our country ever since, but he knew what he wanted and didn't care who stood in his way. There is more to running the United States than just knowing how to make money.
Knowing how to make money is a good start toward knowing how to stop spending it for nothing. It also gives the prudent person great leverage in stopping graft and corruption!