"Why do people do what they do?"

Ever since I went to uni to become a psychologist, I've had this question top of mind. I wanted to decipher the human mind. 

Nowadays people often ask me something similar, albeit more personal: 

"How do I figure out what my purpose is?" 

Let's admit it, we all go through phases of maximum motivation and moments of despair. 

In the former case we have a high sense of purpose, we enjoy high levels of energy and are geared to taking action. 

In the latter case, we lack a sense of direction, our energy is deflated and we keep to ourselves. 

While we are proactive and get things done in one state, we are reactive and procrastinate in the other. 

Same person - yet a different dynamic! 

Why?

We're back to the topic of having a clear purpose. 

With it, the world is our oyster. We naturally are poised and have a "can do" attitude. Nothing seems too major. 

Without it, we feel like a mess. We're missing something... And we give up before we even star...