Retirement is not appealing. I have seen sloth in it, time and again. That said, for those who like it, should enjoy it.
I believe that the truth is, that every man is happiest when he is useful and using his time till his last breath. May not be work, may be a pursuit of unfulfilled dreams, may be a refinement of life long work but greatness lies in looking ahead to living till the last heart beat.
Until we become immortal, and even then.
For as of now, we have at best 36525 days to live.
That tiny spark of our life is precious and can be an ever brighter source of light.
So we end like stars.