Thanks Erik. I think it's a huge problem, you're right. A lot of people go through life never bothering to figure it out either. But the first question can be found by trying to fill the sentence. If your goal is to lose weight, you can say
"I want to lose weight because I'll feel better"
"I want to lose weight because I'll have more energy"
and keep going. Eventually, you'll start to figure out the real reason behind your goal and hopefully discover your why. Maybe not everybody but it's helped me in the past :)