Life's Contradictions

All these sayings and quotes relating to life are so contradictory. We're told that we shouldn't waste our time doing things we don't want to because, life is too short. But at the same time, you need to learn to do things you don't enjoy because not everything in life is going to be enjoyable. Both quotes are incredibly true but very contradictory, and you'll find this is a reoccurring theme throughout life.
So what does life want? Everything, and nothing. It's a confusion. Life wants us to enjoy it, to fill it with what makes us happy, but at the same time it wants us to learn that that can't happen all the time. I suppose what it's really telling us is that we can't always get what we want, but it wants us to try to anyway.
*sigh*