I grew up on our family farm and my grandpa was tough old German immigrant who had all these sage old saying (often laced with colorful language, swear words in German). But most of that old wisdom and sayings all turn out to be true as ever today I think.
He would say things like:
Doing something the right way is hard work, but not as much work as doing it again because you screwed it up the first time.
Or if someone, a farm hand or whoever (sometimes me) would be struggling to figure out how to do something (e.g. get the tractor engine going) he would ask if you wanted him to do it for you, if you said yes then he would call you a nutzloser scheist (useless shit) or something like that. The correct answer was no, please tell me how sir, or something along those lines.
He told me, if you hate farm work you better do good in school so you can get a good job, become an engineer, then you won't have to come back here and work like a dog all day.
He had a lot of them like that, it stuck with me. Sorry I don't have any famous people to name.