The scientific reason why
Psychologist don’t tend to agree on much, since they are coming from different angles; but one thing they do agree on is that one of our basic human needs is to feel a sense of autonomy. We are more happy when we have a sense of autonomy. That is; we feel that we are in control, or have a significant degree of control in our lives. Whether it is at work, in our relationships, or with our health. If we feel no autonomy, chances are that we will be feeling pretty crap on a consistent basis (aka: ‘out of control’).
The Happiness Tip
Be very conscious of your use of the word SHOULD. In fact I have worked on removing it from my vocabulary all together. Whether it is saying it to myself or to others.