There are many excellent writers today; eloquent, intelligent, capable of creating impressive plots and original characters. But there aren't many great ones. Perhaps this was always the case, but there do seem to have been periods in which there was more great writing than others; the Renaissance, for instance, or the Modernist period.
The rhythms of our media, culture, entertainment, the chemicals we are surrounded by, the water we drink, the food we eat, are mostly diluted, empty, 'pretend'. There is very little physical, mental or soul nutrition to be had. But in order to produce something with substance you have to consume things of substance, endure things of substance and have an appetite for 'substantial' things.
It isn't easy to prove a work of art is worthwhile or has nutritional value, unlike food, water, air and various chemicals. The judgement is personal to a certain extent. Worth is sensed, as T. S. Eliot wrote in Four Quartets, as a 'pulse less strong and stronger'. Great writing is infused with something that could possibly be described as depth or resonance. Here are some other traits of great writing, all no doubt noted by others before me:
1) it is not to do with proficiency or virtuosity; many great works are full of faults.
2) it is often not of the moment and so is not
rapturously embraced at the time.
3) it is unique. I sometimes wonder if that is all great
books consist of: uniqueness; which, in a writer, is no
more or less than having a style (you see the necessity
of having one). Culture today requires that
everything be different - music, and writing, and
fashion, and art - which of course it can't be, and in the
attempt to be different (or the type of 'different' currently in vogue) simply becomes homogenous. Trying to be
original is hopeless; any sort of trying is anathema to
good writing. In The Land of Decoration I am not all that ashamed to confess that I consciously played up to the current love of 'quirkiness' while I was writing the novel, as I wanted the novel to get an agent, to be published, and to do well. And I judged the climate right: people (some; enough) bought into that. In The Professor of Poetry I let myself write partly as I liked, or more accurately, as my instinct was telling me. But only partly; in other parts I again capitulated to the relentless command to spin plot, make readers turn pages, read on; the 'hooks', 'lead-ons', - all the awful accoutrements of creative writing schools up and down the country. And I compromised to an even greater degree in The Offering, so much so, that as one reviewer noted, it vaguely resembles a detective novel.
1) Great writing can't be taught. There is more in common between terrible writing and genius than there is between excellent writing and genius.
5) it doesn't have a 'message', is not consciously trying to say something. It just 'is'. Contemporary examples: Cormac McCarthy, W. G. Sebald, Marilynne Robinson; older examples: Melville, Hemmingway, Kafka, Joseph Conrad, the Bronte's, Faulkner. A writer that straddes both camps is J. M. Coetzee, who, an excellent writer, embedding 'clever' pointers for truffle-hunting literary theorists to talk about (something I myself am guilty of to an extent in The Offering) sometimes gives way, becomes less cerebral and calculated and simply engages with his subject matter, for instance, the land itself, not political and moral issues, his writing touches greatness. For example, a lot of Waiting for the Barbarians, In the Heart of the Country, the episodes where Michaels is adrift or half-conscious in the land in The Life and Times of Michael K). Literature should not be a vehicle to try to change human relations, point out political injustice, concern itself with moral dilemma. It can bring these things to light, but if it doesn' transcend those concerns at some point it becomes tired, lifeless, pointless.
What Makes a Book Worthwhile