Short version: He removed the human element from the story. We don't see Jack Torrance struggle to remain sane and sober, we just see him descend into violent madness.
What Stanley Kubrick got wrong about “The Shining” - Salon.com
You don’t have to dislike Kubrick’s “The Shining” to see King’s point. The two men represent diametrically opposed approaches to creating narrative art. One is an aesthete and the other is a humanist. Kubrick was a consummate and famously meticulous stylist; King’s prose is workmanly and his novels can have a shambolic bagginess. The great theme of King’s fiction is the capacity of the average person — especially working-class or similarly humble men and women — both for evil and for heroism. Although there’s almost always a battle against a supernatural antagonist in King’s books, the best of his novels hinge on the protagonists’ struggles with themselves. In “Doctor Sleep,” it is just as valiant for Danny Torrance — the psychic child character in “The Shining,” now grown up — to stay sober as it is for him to challenge the novel’s Big Bad.
King has always thought Jack Nicholson seems “too crazy” at the very beginning of Kubrick’s “The Shining.” Everything that makes Nicholson’s performance iconic — his grinning, campy, manic nastiness — undermines King’s point, which is that Jack Torrance could be you. We all love Jack Nicholson, but he’s no Everyman. In King’s novel, the Overlook Hotel’s seduction of Jack Torrance is rooted in the nebbishy failed writer’s frustrated desire to be extraordinary, larger than life. It’s impossible to imagine Jack Nicholson wanting to be anyone but himself. In Kubrick’s film, Jack’s madness becomes that of an imperious auteur, convinced of his own importance, running amok and seeking to wipe out the mere human beings whose inconvenient presence muddles his vision. That two such different men as King and Kubrick were able to see themselves in this character indicates what a remarkable creation Jack Torrance is.
But while everything in Kubrick’s “The Shining” — especially Nicholson’s suppressed energy — pushes eagerly toward the spectacular release of Jack’s rampage, in King’s novel the man’s disintegration is a tragedy. A key difference between the two versions is the prominence of alcohol, which is more or less incidental in the film. In King’s novel, booze is the key that unlocks the monster inside a regular guy, and the beast’s first victim is the regular guy himself. The most significant thing about any character in King’s fiction is how he or she responds to such monsters, whether they come from within or without. That’s surely the chief reason why he detests Kubrick’s portrayal of Wendy as a gibbering victim; King’s Wendy chooses to be a heroine.
King is, essentially, a novelist of morality. The decisions his characters make — whether it’s to confront a pack of vampires or to break 10 years of sobriety — are what matter to him. But in Kubrick’s “The Shining,” the characters are largely in the grip of forces beyond their control. It’s a film in which domestic violence occurs, while King’s novel is about domestic violence as a choice certain men make when they refuse to abandon a delusional, defensive entitlement. As King sees it, Kubrick treats his characters like “insects” because the director doesn’t really consider them capable of shaping their own fates. Everything they do is subordinate to an overweening, irresistible force, which is Kubrick’s highly developed aesthetic; they are its slaves. In King’s “The Shining,” the monster is Jack. In Kubrick’s, the monster is Kubrick.
King told the BBC that he’d met Kubrick just once, during the filming of “The Shining,” and that he found the director “compulsive.” His distaste is evident, if unstated.
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