balls-up vs damp squib

balls-up

noun
  • Something which becomes muddled or botched in some way. 

damp squib

noun
  • Anything that doesn’t work properly, or fails to come up to expectations; a dud. 

  • A firework that has been wet and therefore fails to go off correctly. 

How often have the words balls-up and damp squib occurred in a corpus of books? (source: Google Ngram Viewer )