My dad said he’s getting tired of working? Is that normal?

My dad is about to be 65 next year. He’s 6 years away from being 70.
My dad said he’s getting tired of working. Wasn’t he the one that encouraged us to get our butts up and get a job? My dad flat out told me he was sick and tired of me looking for volunteers jobs and get a job that pays me and he doesn’t wanna hear that volunteer shit anymore. He doesn’t think it’s bad to volunteer but he said it will not get me anywhere during life. Anyways why is he getting tired of working? He said he’s been working since he was 13 (1969). 13 is very young.