I've heard we want what's bad for us.
Just like a candle. It's purpose is in vain unless a spark gives it life. A candle yearns for a flame, yet once lit, it slowly melts into a puddle of wax. What it needs to meet it's objective, the very reason why the candle was made, will ultimately bring it to it's demise. I tell myself it will be different, that I won't let myself slowly burn out.
I've also heard we want what we can't have.
Something just out of reach seems so much more alluring than when it's simply put in our lap to enjoy. I watch as I am so close to grasping what I want, but it slips through my fingers every time. Do I realize my attempts are in vain and give up? No, instead my desire for it grows. So I'll keep clenching my hand around thin air.