"Without consulting or confronting his co-creator, Kubrick cut a huge amount of Arthur’s voice-over explanation during the final edit... As it turned out, Arthur did not get to see the completed film until the US private premiere. He was shocked by the transformation. Almost every element of explanation had been removed. Reams of voice-over narration had been cut. Far from being a pseudo-documentary, the film was now elusive, ambiguous and thoroughly unclear. Close to tears, he left at the intermission..."
(full article: https://www.newstatesman.com/culture/2017/01/close-tears-he-...)