What's undisciplined about working 6hrs a day, which was about standard for most of human history? Parents (especially immigrants) make incredible sacrifices so

What's undisciplined about working 6hrs a day, which was about standard for most of human history? Parents (especially immigrants) make incredible sacrifices so that their kids don't have to kill themselves with work, not to be an example. And some parents just don't like their kids and use "sacrifice" as an excuse to have fun at the office.