Expectation have similarity as being judgmental in daily routine. For example when You wake up, You wake up, You expect that You can walk. That we take for grant, but we should not ! When You can walk, they You suppose to be grateful that You can. We take for grant A LOT in our life, because we are programmed like that ! Because humans act as copy of God. So, everything good what happens it is expected ! So, if something not good or even bad happens, we are disappointed.
So, majority people in western civilization EXPECT A LOT. And when we get something, it is ours, belong to us and we expect that remain ours...
All of that is wrong ! Because we are just passengers trough this space - time. In brief we are spoiled and immature by design - western narcissistic, materialistic world...
And worst thing that we are hard code programmed - subconsciously ! And even we understand rationally it is very hard to dismiss that auto pilot - complex. When something happens what we do not expect our complex kicks in and produce a lot bad feelings, if we cannot deal with them on healthy way then we are in time screwed !
Being modest and grateful is virtue. Huge difference is between expectations and hope. Hope is our soul projection, and it is pure, good and positive !