I'm an atheist, so the question is nonsensical for me. But, if I am wrong and there's a god, then some people say that the universe is something that God is dreaming in this moment, something that is happening inside his head. Then it's not why God created us, but it's that God cannot control his dreams, same as humans can't control their dreams (except if you're lucid dreaming). If that's so, it's a hell of a long dream, and if God awakes, it's game over. It could also be that God has the Universe for amusement, same way that some people have aquariums filled with multicolored fishes and structures. the last option that i see is that the universe is some kind of experiment by God, maybe he wanted to create life and got the Universe that we see, and maybe now that he has experience, will destroy it in order to create another universe where life is more complex. The explanation that I see absurd is that he created the universe in order that people would adore him, in that case it would be an arrogant God, and not very benign, given all the disgraces that he has invested on our planet.