Let's say I own a building which I'm renting for $10M/year and I employ 10 people to service the building. Are these employees "bringing" me $1M on average? Or

Let's say I own a building which I'm renting for $10M/year and I employ 10 people to service the building. Are these employees "bringing" me $1M on average? Or maybe the main factor is that I own a building, worth millions? Anyway, I know you were not serious about the $1M figure. That wasn't my point either. All I'm saying is that the expected value of your work <= your salary. And sky isn't the limit for that number so employers have to take this into account.