[sandspar]

I've found that early retirement tends to be bad for people who have the combination of "high need for achievement" and also akrasia (the condition of being occasionally weak willed). If you are someone who has a mismatch between "how much I want to achieve" and "how much I can force myself to do annoying things", then early retirement probably isn't for you. If you want to achieve a lot, and can force yourself to do annoying things, then you'll probably be fine in retirement. I know an ex Army guy who still wakes up at the same time as he did while he was in command at his base - he does fine in retirement. What ends up happening for lots of people is that they still want to be competent, but without the external goad of work and deadlines, they're unable to force themselves to do hard things.