The world exists because God desires that there be an other, and so love is fundamental to that.
Maybe it exists because god loves to create universes. Maybe the development of life is incidental to his love of creation; an interesting but ultimately discarded artifact of his fondness for causing worlds to form from the expansion of a singularity (or twirling them into existence out of thin air, if this is his preference).
At the same time, a being who is utterly unlike us might create universes and worlds and people without a shred of motivation. Perhaps this is god's true nature-- he wishes universes into existence, then loses them in the clutter of his home, where they tumble about until they run out of energy and disappear in a puff of magic.