Well, it's possible for them to retire when thet are really of age and can't handle the business any longer, then they may pass the business to their family members but in most cases , they pass it on to their children who then later continue running the business.Most organizations have a set limit for how long their staff can work, especially in government establishments. Some people only retire though because it's necessary.
What of those who run their own businesses without external control? Is it possible to retire?