If you come face to face with some really challenging situations and tragic circumstances - you are going in there with a purpose. You are not going in there as a tourist.
Our ancestors are totally essential to our every waking moment, although most of us don't even have the faintest idea about their lives, their trials, their hardships or challenges.
As you get older, there will be a new challenge arising. What you thought you'd accomplished once, maybe the goal post has shifted and it's not what you're pursuing anymore, because you're not interested in that anymore, you know?