Q:Why there is creation?
A: Creation is the dream of consciousness in which consciousness itself is present in many forms. Here is an analogy to understand this:
Consciousness is (say) Vishnu, Vishnu sees a dream (say, Brahma) in which he himself is present in many forms. So, you the questioner is a dream object in Vishnu’s dream. When this dream is over one can say that Shiva has destroyed the world. Here Vishnu, Brahma and Shiva are used as symbols meant for explanation purpose. Vishnu symbolises pure consciousness, Brahma symbolises creation (i.e. consciousness in dream or under ignorance), Shiva symbolises destruction of dream/ignorance. One can use different symbols if one wants to.