My personal opinion is that everyday is a once in a lifetime opportunity to do something.. once that day is gone.. you can NEVER get it back!
As far as a typical "once in a lifetime opportunity" It would have to be not quitting my job sooner to spend more time with my father before he passed away.. a few weeks sooner.. a day sooner.. one hour sooner.. just the chance to have been able to spend more time with him..
Hindsight is always 20/20 and I think that a lot of "once in a lifetime opportunities" do not present themselves as such until they have past..
