Hindsight means the opportunity to judge or understand past events using knowledge that you have gained since then. The 20/20 indicates vision sharpness or clarity. This proverb refers to retrospection. You may not always have ‘the clearest vision’ when you are making a decision, but given a little more time, your ‘vision’ seems too clear. That’s why anything in hindsight (retrospection) is always seen more clearly with 20-20 vision. This proverb is also used in an ironic way to mean: ‘It is easy to be wise after the event.‘
