Hoover -- Hooverville
Dewey -- "Dewey defeats Truman"
Nixon -- Watergate
Saddam Hussein -- Iraq War
Benedict Arnold
Marie Antoinette
Nixon is of course known for Watergate.
Benedict Arnold is known for his betrayal.
Saddam Hussein invaded Kuwait with the intent of dominating the Middle East in the name of Arab nationalism and Islam. He believed the US would not wish to get involved. Yet, it united the UN including Egypt and Syria against him, leading to his defeat. Instead of being renown for bringing forth Arab nationalism, his actions set forth a chain of events which eventually would not only lead to his own end but the ends of fellow Arab nationalists.
Marie Antoinette is a perfect example. With France in decline, the king became depressed from the pressure, and she became more involved in the politics partly to help ensure a future for her children in the French monarchy. Yet nearly every thing she tried to do resulted in the opposite. She was an easy target for rumor and criticism and as a result she is remembered today for things which historically she didn't do and didn't say. And ultimately not only did her children not rule, but the monarchy itself was abolished.
My favorite though is Hippias, the last tyrant of Athens. He was so disliked that his opponents invented Democracy in order to avoid someone like him becoming the dictator.