“Hindsight is 20/20” is an idiom that means it is easier to understand something after it has happened than before it happened. The phrase is often used to describe situations where people realize what they should have done after the fact, but it is too late to change the outcome.
For example, if someone makes a poor investment decision and loses money, they might say “hindsight is 20/20” to express that they now understand what they should have done differently.
The phrase “20/20” refers to the clarity of vision measured by an eye chart test. A person with 20/20 vision can see clearly at 20 feet what should normally be seen at that distance.
