Some interesting responses here…
I retired some years ago.
For me the decision was straight forward. I was content with what I had achieved and was in a fortunate position to explore other interests.
My post was prompted by SWMBO who recently saw the question ‘when do you know when it’s time to retire?’ posted on a forum following the recent ruthless round of global I.T. layoffs – the responses were wide and varied and could largely be categorised by age and ambition.
Instinctively I think you know when the time is right.