hindsight is 20/20

From the term 20/20 referring to normal visual acuity.

hindsight is 20/20

1. (idiomatic) In hindsight things are obvious that were not obvious from the outset; one is able to evaluate past choices more clearly than at the time of the choice.
   • 2009, Joseph Grcic, Facing Reality: An Introduction to Philosophy, Revised edition, Bloomington, IN: AuthorHouse, page 57:

     Another common error dealing with memory is that of "hindsight bias." This is the tendency to exaggerate what could have been anticipated in the past. This is also known as "Monday morning quarter backing" or "hindsight is 20/20" where the "right" decision as to what should have been done appears to be more obvious now than it was in the past.

   • 2023 July 30, Gretty Garcia, “Coco Gauff Is Still a Teenager, but Her Net Worth Reveals That She’s Already a Millionaire”, in Cosmopolitan‎:

     Honestly? If you would have told me that becoming a professional tennis player might net me a decent supply of free pasta, I would have never begged my mom to quit my lessons. 😭 Hindsight = 20/20.

• twenty-twenty hindsight

• Monday-morning quarterback
• it is easy to be wise after the event