dud vs might-have-been

dud

noun
  • A loser; an unlucky person. 

  • A lottery ticket that does not give a payout. 

  • A failure of any kind. 

  • A device or machine that is useless because it does not work properly or has failed to work, such as a bomb, or explosive projectile. 

might-have-been

noun
  • Someone or something whose potential greatness was not achieved. 

How often have the words dud and might-have-been occurred in a corpus of books? (source: Google Ngram Viewer )