Time, Roger Waters' Ghost of Christmases Past and Future

When I first got into Pink Floyd, the song Time, from Dark Side of the Moon, was the one that hit me hardest. There are people out there better equipped to discuss the musicality of that song, but for me, it was the lyrics that held personal meaning.

You are young and life is long, and there is time to kill today
And then one day you find, ten years have got behind you

No one told you where to run, you missed the starting gun.

I was probably fifteen/sixteen when I first HEARD that song, and it resonated with jarring effect. Not because I could relate at that early stage of life, but because it felt like an A Christmas Carol style warning.