incompleteness vs incompletion

incompleteness

noun
  • The state or condition of being not complete. 

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. 

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