It is true though. You don't know what you have. Ever. And then its gone. Its a stupidly abstract concept to try and know the worth of something before you lose it. Before whatever is important to you goes away. Or is taken away. Or is lost. Once its gone, then you know how valuable it was. And then, most times, its too late. Its only by reflecting on what you've lost, do you know the worth of what you once had.