One of the things that I do to generate ideas for Cant columns is to read Excite's Odd News section. There's often something rant-inducing there. Such as this story: "Hugo Family Slams 'Les Miserables' Sequel".
The problem with crappy sequels to great books and movies is that they diminish the original. Gone With the Wind remains a great work, but now it's associated with a mediocre follow-up novel. These works just don't need sequels written by cut-rate authors. (Don't quibble that the author of the aforementioned novel died before being able to write a sequel; at least it would have been the original author writing it. Just press on, and I'll address the point in a minute.) If the author wanted to continue the story, they would have done so. It's not as if authors don't churn out crappy sequels to their own works all the time. That's the basis of Piers Anthony's and Terry Pratchett's careers. Even good authors can get sucked into it: look at how Asimov went sequel-happy with his Foundation series, and the sheer volume of sequels to Dune. However, many authors manage to restrain themselves. If anyone should have been smitten by the idea of sequels, it would have been Dickens. Maybe the idea just never occurred to him. And Shakespeare could have made his life easier by just writing Macduff the King and More Ado About Nothing (yes, I know, Henry V is, technically, the sequel to Henry IV parts I and II; but Henry V is far superior, and a solitary case).
Or maybe, like Victor Hugo, their works told the story that they wanted to tell. Hugo obviously didn't feel the need to write Les Miserables II: Even More Miserables. But sequels are easy: you take the same characters, and continue with the same situations. You're not telling a new story, you're simply extending the old one, hopefully extending it enough to fill a book.
But this isn't really about authors writing sequels to their own works; I really can't fault a writer for wanting to do that, as long as they don't become too captivated by their own characters, unwilling to ever let them go. No, this is about authors writing sequels to works that are not their own. Why do I assume that the sequels are going to pale in comparison to the originals? Because they're written by hacks. Good authors have their own ideas, and aren't satisfied by rehashing someone else's characters and situations. And all too often the new writers try to "fix" things: the Les Miserbles sequel is described as "an action-packed adventure story based on the premise that Javert, the villain of the original novel, lived on and turned into a model hero." Great. So it turns out that in the original novel, Javert was just conflicted, or misunderstood, or, I dunno, extremely constipated. Or he just needed the love of a good woman. That's always a popular one. As the title of the new bastardization is Cosette or the Time of Illusions, I'm guessing it's the love of a good woman thing. Yeah, I bet that's just what Victor had in mind. The original novel was good, but it was oh so depressing. So let's write a sequel, turn that nasty old Javert into a good guy, and give the series a happy ending! Yay!
Sure, you can argue that I'm being cynical, and rushing to judge the book before it's even been published. But the Hugo heirs make a good point: "Does anyone think someone could commission a Tenth Beethoven Symphony?" Of course the answer is No, and the world doesn't need one. It might be less risky to stick with proven winners, but it's also far less interesting. The results are usually disappointing, at best. The world doesn't need another Beethoven, or another Shakespeare; it needs new artists to join the ranks of the greats. Not to merely regurgitate old ideas, but to add new ideas and artistic experiences. There's always plenty of hacks waiting to feed on the scraps of genius.