effectiveness vs weakness

effectiveness

noun
  • The capacity or potential for achieving results. 

  • The degree to which something achieves results. 

  • The property of being effective, of achieving results. 

weakness

noun
  • An inadequate quality; fault 

  • The condition of being weak. 

  • A special fondness or desire. 

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