last straw vs misstep

last straw

noun
  • A small addition to a burden which causes it to exceed the capacity. 

misstep

verb
  • To step badly or incorrectly. 

  • To make an error or mistake. 

noun
  • An error or mistake. 

  • A step that is wrong, a false step. 

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