Editing, done by an other, provides a check and balance against two common inclinations found in self-published expressions: the inclination to make public what is essentially private, and the inclination to attract attention by being vulgar. The first of these inclinations overvalues a kind of narcissism, and the second devalues hard work and difficult concepts.
An editing process reminds the author of his / her responsibility to audience and to art itself; a good editor corrects the author's natural inclinations and raises expectations for art.
An unchecked and unbalanced emphasis on needs of the individual over needs of society can result in decreased value for editing. Also, consider how tired and banal are iterations of themes of human sexuality in a vacuum of rigorous editing.