Context : Relationships, Social Life
20/20 vision the standard measure of visual acuity (clarity or sharpness) in the United States. If you have 20/20 vision, it means that can see from 20 feet what should normally be seen at that distance. If you have 20/50 vision, it means you see at 20 feet what a person with normal vision can see at 50 feet.
Usage of “hindsight is 20/20”
I see now the signs of her cheating on me. At the time, I was blind to it. Hindsight is 20/20.