Based on Bhagavad Gita Chapter 18, Text 58
In youth, we are mostly in a state of hurry, having so many things to do and imagining that we can bend the world to our will.
In middle age, we are mostly in a state of worry, having learnt through life’s hard lessons that so many things may go wrong and fearing that we may not be able to control them.
In old age, we are mostly in a state of feeling sorry for ourselves, lamenting all the things that we did wrong or all the things that went wrong despite our best efforts.
The Bhagavad-gita outlines this unfortunate life-trajectory when it declares (18.58) that those who refuse to connect with Krishna will suffer and perish. The same verse offers a far better alternative life-trajectory when it states that those who connect with Krishna will pass over all obstacles by his grace.