Lot's of scientists and engineers and physicians are still doing what they know best. These kinds of knowledge and skills do not go away with age, and since pra

Lot's of scientists and engineers and physicians are still doing what they know best. These kinds of knowledge and skills do not go away with age, and since practitioners of these arts are constantly learning new things, and looking for better solutions to problems, people in these fields often work until the very day that death catches up to them. Programmers tend to be just like these other STEM like professions. Although with age we tend also to broaden our horizons a bit, perhaps into genomics or massively scalable systems or new approaches to cyber security.