I'm sorry, but I did not understand your comment at all. Some of those sentences don't parse for me. I don't know what you're trying to say. Can you please clarify?
It seemed clear enough to me. Your salary is less than or equal to the value you add (companies will usually not knowingly pay you more than you’re worth), not equal to it.
The rest was expanding on that core point by computing the expected profit a company gains by hiring someone (value - salary [minus total costs, actually]) and that a company will seek to maximize its profits.
I guess I was confused by the use of the pronoun "it" right at the beginning. With no context, I had trouble deciding what it mean, or deciphering much of the post. What you explained is the only bit I was able to guess at on my own, mostly because it's common sense.
The part about the mathematical viability of fairness was particularly quite puzzling.
I read the initial it as “your salary = your value add” giving a single point figure which is the upper bound of the inequality “your salary <= your value add” and the upper bound on what a sound company would pay.
(It’s actually higher than what a sound company would pay, but if you switch salary out for “total cost to company”, it becomes correct again.)
