Some people think that the creation of the world by G-d is like a human creating something, which after he is finished the creation does not need the creator in order to continue existing. But, this doesn't make sense, because when a human being creates something, he makes it from something else. Therefore, when he leaves, the creation stays the way he made it. However by G-d since he created the world from nothing, in order to keep it exciting, he must be there holding it up the whole time.