In my world, my goal and my expectations are only indirectly related. My goal is always a championship, but my expectations are to be clean, competitive, etc. So, my ultimate goal and my standard expectations may never "meet" in the sense that my goal may never be accomplished. Winning it all is my goal, but not my expectation. In other words, he can be a successful long time coach in my view and never win it all.
As for salary, I would let the market set his salary. Assuming he is meeting expectations (so that he is eligible for retention), if he demands more than market, he would need to decide how much he really likes it here. If he's not meeting expectations I don't want him. I would be willing to pay market to keep a coach I want. If he is wanted but wants too much money, I guess he would walk.
Finally, if my expectations are set to what I want when we start the journey, they won't go up or down with longevity. They are what I expect. Meet them and stay. Fail and bye bye.