Peter Segal is a writer, director, and NPR personality. Back in the 90s, Peter Segal wrote a screenplay called Cuba Mine, a love story set against the backdrop of the revolution. A studio purchased the script, but thought, according to Segal "Well, you know, today's audience doesn't want to see a lot of politics and an elaborate discussion of the flaws of the Batista regime. They want dancing and sexy fun." So the studio cut out all bits about politics and replaced them with dancing, and called the film Dirty Dancing: Havana Nights. Segal's pretty good-natured about the whole thing.
George Lucas, not so much. Lucas managed to squeeze out three amazing Star Wars movies before it all collapsed under the crushing weight of his massive ego. Lucas was openly disdainful of fans who hated his re-releases of the original films and flat-out refused to allow the unedited originals to be released on DVD. And when fans hated the prequels, he blamed the fans for their lack of taste. So it should come as no surprise that when Disney and JJ Abrams resurrected the series with a wildly popular 7th installment, George Lucas hated it. In an interview, Lucas complained he'd sold the film to "white slavers" but conceded, disdainfully, that fans were sure to love it. Then he blew his nose with a wad of $1,000 bills courtesy of said fans and was carried, sobbing, out of the room in his titanium sedan chair.
When it comes to film adaptations, Stephen King's work has seen some big winners and some spectacular losers.
or Attack of the Flying Vaginas
or The Monster That Ate Bronson Pinchot's Career
Given that his Sometimes They Comeback... Again is the only film I've ever seen to score a Rotten Tomatoes rating of 0%, you may be surprised that there's only one movie he says he really hates: The Shining. For a young Stephen King, having the great Stanley Kubrick show an interest in adapting King's third novel must have seemed like a dream. But the happy haze didn't last long. Kubrick hated King's version of the screenplay and made sure King and everybody else knew it. He decided rewrite the screenplay himself, and rewrite he did, over and over and over again. Though the plot remained largely the same, the characters were drastically different, and that's King's beef. In a BBC interview, King said "Shelley Duvall as Wendy is really one of the most misogynistic characters ever put on film, she's basically just there to scream and be stupid and that's not the woman that I wrote about." And screaming stupidity was exactly what Kubrick had been going for. Kubrick was a horrible bully to Shelly Duvall, criticizing her harshly and forbidding the cast and crew from showing her kindness or sympathy. He made her film scenes over and over so that Duvall was overcome with exhaustion and had to drink tons of water because she was literally dehydrated from crying. By the time the film was over, Duvall was losing her hair in clumps and had become seriously ill.
That's one upside to being a technical writer - you don't tend to get emotionally attached the the stuff you make. The downside, of course, is that you don't ever get to do anything worth feeling emotions over.