I hesitate linking a Psychology Today post because it seems like the magazine has just become an ad service for pop psychologists selling their books.
But I've read Heidi Grant Halvorson book, and she seems to do good research.
My summary of this idea based on reading her book:Most people in every workplace, classroom, or community on the planet belong to one of two camps. In Camp #1, there’s Jon - the kind of person that some people might call “difficult,” though probably he (and we) would prefer the term “skeptic.” It is a challenge to get to the end of a sentence in Jon’s presence without having him interrupt you to tell you how the beginning of it was all wrong. He is immaculate in his appearance, chooses his words with precision, and never procrastinates. He is, by nature, a pessimist (the defensive kind that we describe later) – try to tell him things are going to work out just fine and watch as he gets visibly uncomfortable with your reckless and naïve attitude.
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-Promotion focus makes you more excited as you get close to your goal (of promoting something into your life), but completely deflates you when you are far away.
-Prevention focus makes you more anxious and energetic as you get furthest from your goal (of preventing something from entering your life), and leads to calm state and less energy as you get close to completely preventing something from your life (and possibly loose steam).