When you use this phrase twice in one day.. you know something is definately wrong!

taken from www.phrases.org.uk,

20-20, more often written 20/20, is the standard for clear vision. When an eye doctor measures eyesight, a reading of 20/20 represents clarity. Hindsight, looking back on what has already happened, allows us to see clearly the course of action we should have taken, but perhaps didn’t. So … if you nag me with what I should have done yesterday, I will gently remind you that your hindsight is 20/20, but where was all this good advice when I needed it?

I think that sums it up quite nice…..