Since I retired, many of these kinds of quotes apply:
I have retired, un-retired, and retired again all in the past 10 years. I find the biggest trouble with having NOTHING to do is . . . you can't tell when you are done.
The best time to start thinking about your retirement is before your boss does.
I'm not retiring from life, just a job.
Advantage of retiring at 65; Most of the people that I owe apologies to are all dead.
Disadvantages; I now have to read the newspapers on my own time.
....and last, but not least:
Before retiring early from your job, stay home a week and watch daytime television. ( I STILL wont watch any daytime or even much evening contrived TV garbage)