Outcome independence

There's often an inverse correlation between how much you want a certain situation to pan out and how it actually pans out.

Consider the interview for the job you don't care for, versus the one you absolutely, positively do. Wanting a certain outcome can cause you to overprepare, or worse, to cause your performance to suffer. Not caring so much about the outcome frees you to focus on having a good interaction with the person(s) you're with, actually learning something from the encounter, and ironically, having a better interview.

Or consider the guy on the date who's so afraid of what she'll think that he fumbles with his words, neglects to smile, and loses her interest entirely. Instead, it's the bad boy archetype--the guy who cares less (or, more often, who simply cares more about other things)--who attracts the girl.

The point isn't that you shouldn't care, or hope for a good outcome. It's asking whether acting like things need to turn out the way you'd like them to will help or hinder your chances that they actually will?

Because, if it's not going to help, why do it?