complication vs motive

complication

noun
  • The act or process of complicating. 

  • A person who doesn't fit in with the main scheme of things; an interloper. 

  • The state of being complicated; intricate or confused relation of parts; complexity. 

  • A feature beyond basic time display in a timepiece. 

  • A disease or diseases, or adventitious circumstances or conditions, coexistent with and modifying a primary disease, but not necessarily connected with it. 

motive

noun
  • A motif. 

  • A motif; a theme or subject, especially one that is central to the work or often repeated. 

  • An incentive to act in a particular way; a reason or emotion that makes one want to do something; anything that prompts a choice of action. 

  • Something which causes someone to want to commit a crime; a reason for criminal behaviour. 

verb
  • To prompt or incite by a motive or motives; to move. 

adj
  • Relating to motion and/or to its cause 

  • Causing motion; having power to move, or tending to move 

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