incompletion vs ineptitude

incompletion

noun
  • The state or quality of not being complete. 

  • A forward pass which is not caught inbounds by the intended receiver. 

  • Something which is not completed. 

ineptitude

noun
  • The quality of being inept. 

  • An instance of being inept. 

How often have the words incompletion and ineptitude occurred in a corpus of books? (source: Google Ngram Viewer )