Exactly. The utility of income is not linear. The first 10,000 dollars are much more useful than going from 190,000 to 200,000 a year. That's why the tax system has a progressive structure. If you want me to work 10% more then you need to pay me more than 10% more.

And that does not even consider that my free time is very limited. If I have say 2h of completely free time everyday (24 hours minus work, commute, chores, gym, household crap, etc) and I need to work just 1 hour per day longer, then that cuts my free time per day in half. That is HUGE. You better pay me a lot for that.