incubation vs qualification

incubation

noun
  • One of the four proposed stages of creativity (preparation, incubation, illumination, and verification): the unconscious recombination of thought elements that were stimulated through conscious work at one point in time, resulting in novel ideas at a later point. 

  • Sitting on eggs for the purpose of hatching young; a brooding on, or keeping warm, to develop the life within, by any process. 

  • The development of a disease from its causes, or the period of such development. 

  • A period of little reaction which is followed by more rapid reaction. 

  • Sleeping in a temple or other holy place in order to have oracular dreams or to receive healing. 

qualification

noun
  • An ability or attribute that aids someone's chances of qualifying for something; specifically, completed professional training. 

  • The act or process of qualifying for a position, achievement etc. 

  • A clause or condition which qualifies something; a modification, a limitation. 

  • A certificate, diploma, or degree awarded after successful completion of a course, training, or exam. 

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