In an earlier post on this blog (from 2009), Y-H-B pointed out the increasing tendency in English speech and writing on both sides of the Atlantic to mistakenly substitute the word “final” for the the traditional and normative “last” in the phrase “the last straw.” This speech error has penetrated even scholarly writing, as I witnessed today in rereading a book on Tchaikovsky by a British author, John Suchet, who uses “final” instead of the traditional “last” more than once.
This mistake is an illustration not only of hypertrophy (v. my earler post) but of lack of historical knowledge. The complete phrase is “the straw that broke the camel’s back” which comes from an old Arab fable.