Why do people write? It is because they want to express something. Some feeling, emotion, thought or all that in a pile. Whether they write a story, or novel, the characters in it will bear certain qualities - virtues or faults - that the author appresiates or denies. You may not say it directly, but your opinion can be perceived between the lines.
Furthermore, each story, essay or book is intended by the author to make some impression, to raise question or to give answers, and all these refracted through author's personal prism. It is true that almost nothing on this world is new and unseen, and that everybody has read or heard about the topics he writes about elsewhere. Each author makes research on his work before writes on it. The important point is, whether his work bears new aspects or follows the shades of his predecessors.
So to me literature is always subjective.