Are High Expectations the Enemy of Happiness?

Many marriage experts say that high expectations are the enemy of happiness in marriage. You come to a slightly different conclusion, saying it's true that many marriages might be unhappier than they were half a century ago. Who are the exceptions? The exceptions are people who bring those expectations and are able to meet them. This is, as i think, the crux of the entire issue. Lots of people argue that having these high expectations is problematic and its harming the institution of marriage. And frankly, among the people who used to gue that is myself.