Because my favourite books are probably A Song of Ice and Fire. And Game of Thrones started so well.
Then they changed Asha. And destroyed Robb Stark's parallel with his father. And made Brienne and the Hound fight. And casually killed Jojen.
I do think the Red Wedding works better on the show, though. And the opening is always good. But, yeah. I don't watch GoT anymore.

(am i the only one desperate for winds to come out i hope not)

But in all honesty, I do like some book movies. The Hunger Games movie, for example, was very well done. I also liked Harry Potter and the Deathly Hallows pt 1.

I also am a fan of the Marvel Cinematic Universe without having read many (if any at all) comics starring its superheroes, and adore the How To Train Your Dragon movies in their own right, knowing pretty much nada about the book series (to be fair, the movie doesn't really have much in common with the books).

Seeker: The Dark is Rising is the worst film adaptation of a book ever. I'd say that as an irrefutable fact. Not only did it almost completely ignore the premise of Susan Cooper's The Dark is Rising Sequence but it is quite possibly one of the worst films (not films are based off of a bad book, or the bad adaptation of a book, just films in general) ever made.

List of things the film adaptation redacted:
-Connection to Celtic Myth.
-Connection to Arthurian Myth.
-The protagonist's nationality which is tied to the Mythos.
-The entirety of it's Mythos.
-The protagonist (NO, HE WAS NOT "AGED UP". Book!Stanton and Movie!Stanton are two completely different characters).
-Removal of The Walker.
-The first book.

List of things the brilliant Hollywood Producers shoehorned in a hopeless bid to compete with the Harry Potter films
-Protagonist is a teen that only cares about girls and getting superpowers.
-Protagonist is now an American
-Trying to instil immediate sympathy for the protagonist by sicking bullies on him.
-Trying to instil sympathy for the protagonist because he is an American in a "foreign" country.
-Trying to instil sympathy for the protagonist because his family is essentially the Dursley's but with the numbers of the Weasley's.
-Christopher Eccleston, who left Doctor Who and walked face and eyes into this.
-Vikings, because why not?
-Ineffectual villains
-a 90 minute run time
-and various other Book-to-Filmisms

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Let me explain.

First of all, I know that the Harry Potter fandom has problems with Cassandra Clare. Honestly, I have never read her infamous 'Draco Trilogy' and I've seen this movie first. It interested me enough to read the books, and I sincirely enjoy the world Clare has created. It's not the best world I've ever seen, but definitely interesting and original one. Now, about the movie itself...

It's mediocre. It is not very good, simply because the first book is not very good. I realize it may contradict my previous statement but yes - The City of Bones is probably the worst opening book of any series I've ever read. Well, with a TV show hitting ABC Family (or, "Freeform") early January, I've decided to re-watch the adaptation from 2013.

The effects, the scenery, and the visuals - all of those deserve a praise. Especially nicely done were scenes in the Silent City, and at Magnus Bane's party. The casting works... for the most part. Godfrey Gao makes a spectacular Magnus Bane, Robert Sheehan is an adorkable Simon Lewis, and I will always praise Jemima West's Isabelle Lightwood (I would let that leather-clad huntress take her whip and... Umm... you didn't see that!). Unfortunately, there are some miscasts: Kevin Zegers seems too old to be playing Alec Lightwood, and Aidan Turner doesn't exactly struck me as Luke Garroway.

Now, what doesn't really work is the acting. While the lines themselves were really nice ("Downgraded from a gingerbread house to a one bedroom?
Overall, I'd give The Mortal Instruments: City of Bones 3 out of 5 starts.

I can understand why other people might not, but I for one actually found them to be quite decent. I do think that there was quite a lot of wasted potential with regards to the storyline and character development, and I dislike the way quite a few of the scenes were executed (especially in BOTFA), but otherwise I didn't particularly mind a lot of the things which most people have been complaining about (or, at the very least, I could sort of understand the reasoning behind some of the film decisions that were made)? Maybe I'm just overly lenient when it comes to film adaptations, I dunno.

But the movies made from my favorite books? If we're going by favorite (and stuff I've actually seen), then that'd have to be the Discworld made-for-TV Sky One movies. I saw all three -- Hogfather, The Color of Magic, and Going Postal -- after they found their way to Netflix for a time. They ran the gamut from "not bad, I suppose" to "yeesh, what the hell was that?" Some of the details have faded from my memory (it's been a while since I've seen them), but here's what I can recall.

Starting with the best first: Hogfather. Given how convoluted and meta the Discworld books can be, I thought this adaptation was pretty solid. Most of the major scenes were touched upon in some way or another, as best as I can recall. The biggest cuts came in regards to the little gods/personifications that kept popping up. The Oh God of Hangovers was there, but a number of others were not. Some of the stuff with the bandits in the Tooth Fairy's castle was also condensed/altered. Sidney the wizard was the one scared of the Scissor Man, for example.

The casting was solid, with Teatime being particularly creepy. My only complaint in that regard would be that Susan occasionally came across as too stolid sometimes. Particularly in scenes dealing with Death himself.

Notable scene(s): Pretty much anything with Alfred. He had some good reactions to the stuff Death was doing. I also liked the running gag with his trying to make a roll-up.

Right in the middle was The Color of Magic (which technically included The Light Fantastic as well). This one was... I guess weird would be the best way to describe it. The casting was particularly odd. The same guy who played Alfred in Hogfather was Rincewind, which totally clashed considering how relatively young Rincewind is supposed to be. Twoflower was played by Sean Astin, which was just... I mean, he did a damn good job, but come on! Apparently the director chose to satirize American rather than Asian tourists.

To the adaptation's credit, it managed to wrangle the convoluted plotlines of the first two books fairly well. Quite a bit of stuff was cut, such as the Temple of Bel-Shamharoth and the nymphs. The adaptation also explains away why Twoflower seemed to gain such a grasp over Morporkian so quickly despite the big hullaballo there was over his not initially being able to speak it. I love Terry Pratchett, but The Color of Magic (the book) does not exactly hold up. That being said, Astin!Twoflower lacks the sense of gentility and forgiveness that I remember Book!Twoflower having. There's a big scene in the adaptation where he and Rincewind have a falling out.

Notable scene(s): Almost any bit with Sean Astin. Good actor, extremely weird choice.

At the bottom of the barrel, we have Going Postal. This was especially galling for me as I love the first two Moist von Lipwig books (haven't read the last one). There's just so much wrong with this adaptation. The casting is mostly bad, with Moist and Adora feeling out of character at multiple points. Moist in particular lacked the charm and wit I associated with his book portrayal. The best casting decision was having Charles Dance as Lord Vetinari. Bit weird having a blond Vetinari given all the art I've seen, but damn Dance caught the essence of the character.

The plot was also shredded to hell and back. Angua's one appearance outed her as a werewolf almost immediately. The Post Office for some reason was less interested in getting the mail delivered and more with trying to redeem Moist by showing him his crimes. The confrontations between Moist and Reacher Gilt were expanded upon, for the worst. The ending is wildly changed and includes Moist being outed as a conman (thus sinking part of the plot for Making Money). Oh, and get this: Moist's getting Adora fired caused her to start smoking.

Oy vey.

Finally, I know this was a made-for-television production (and thus had a limited budget), but the golems were just hideous.

Notable scene(s): Anthing with Charles Dance. Also, Terry Pratchett's cameo as a postman.

I haven't seen them in a while, though, (and not even all of them; the last one I saw was Goblet of Fire) so I can't be totally sure.

I remember that I liked the Lord of the Rings movies, too; perfect for long car rides to and from the Outer Banks! Now I just need to find Return of the King...

I saw part of the Golden Compass movie on an airplane one time. I don't actually remember how I felt about it beyond "ooo, pretty". Do y'all think it's worth a rewatch?

The Twilight ones were okay, too. Didn't see Breaking Dawn, though; I was convinced it would be a giant R-rated ball of nope for me. Turns out, I was wrong about the rating only. (I was in high school, don't judge me.)

The Percy Freaking Jackson movies. They had a chance to create a second Harry Potter franchise, one where we watch the characters- and therefore the actors- grow up. A franchise with Magic, but set in a modern world.

But instead they give the characters about 5 years of age and little semblance to the original canon or plot

Speaking as someone who genuinely enjoys the Inheritance Cycle books, the Eragon movie is, well, complete and utter fecal matter.

-Angela's role is diminished and bastardized. Angela was a cool, mysterious character and her companion Solembum is crucial to the plot. The movies just made Angela "hey, random fortuneteller" and removed Solembum completely.
-Arya being royalty is actually a really effing big deal, and it's not revealed until Eldest. And she never describes herself as a princess.
-They removed Elva. Elva is, like Angela and Solembum, very very important to the development of the rest of the cast.
-The Urgals are all wrong. In the film they're generic foreign savage types. In the books, they're roughly equivalent to orcs... and they've got a culture.
-No Isidar Mithrim. You'd think a movie, which tends to love big flashy effects, would make a big deal out of a giant red rose made of sapphire, but I didn't get the satisfaction of seeing it.
-The reveal of Brom being a Rider is supposed to be at his death, because it makes his secrecy make sense in hindsight to Eragon.
-The Ra'zac. My god. The freaking Ra'zac. These things were my favorite part of the series, and they were absolutely mangled in the adaptation. In the movie, they're just worms that walk that hunt the heroes. In the books, they're these freaky Lovecraftian horrors that metamorphose into dragon-sized bats (which were ALSO butchered by this movie) that are specifically evolved to be human predators. In the film, they were changed from the enigmatic menaces that saved the books (to me) to black-cloaked minions even more generic than the Nazgul.

Just... eff this movie. The only redeeming quality was the cuteness of baby Saphira.

When I was in graduate school, I was often too busy studying to do any significant reading on major novels and such, so my appreciation of the written word was kind of a mixed bag. When I wasn't studying, though, I was able to find the time to familiarize myself with at least some of my favorite works of literature, such as all seven Harry Potter novels, the original Percy Jackson series, the Hunger Games trilogy, the Warriors series, and unfortunately (thanks to my mom) the Twilight saga. At the same time, though, I missed out on a few other works as well; I still have yet to read the LoTR series in its entirety even though I know the general idea behind most of it, along with the Hobbit novel preceding it - and don't get me started on Animorphs (which I've only read one or two books of), the Guardians of Ga'Hoole (I've only read up to the first three or four books), and the Maze Runner series (which I haven't even touched despite seeing both of the movies currently released).

In light of this, my judgement on how good The Movie is depends on whether or not I know the original source material. If I do, I determine the worth of The Movie depending on whether it's a good adaptation first and foremost, and if I don't, I judge The Movie without reference to the source, unless The Movie is so different from the original subject matter that it could be considered its own story.

This is why I believe that if you play your cards right, The Movie can sometimes be at least as good as The Book, if not better. I believe that there are two key factors: being a good experience for people who don't have the time to read the original source, which movies are generally good at, and attempting to stay faithful to the source itself, which movies are BAD at. Two ways to settle both issues is to make The Movie a work of its own (like the HTTYD movie or The Princess and the Frog as Ix mentioned), and to faithfully adapt every single detail from the source, which is tricky due to the time and budget constraints of most movies but CAN be done (The Twilight saga is sadly one of the rare few that has mostly succeeded in this respect AFAIK). If you try to do both at the same time, the different demands of moviegoers and book fans mean you have to make compromises which can only lead to failure. This isn't limited to adaptations of written works, either - there's a reason The Last Airbender is never brought up within the AtLA fandom, for example.

That being said, I will concede that this isn't necessarily a hard and fast rule, and that sometimes The Movie can still be awesome even if it botches the original book, show, or whatever it's based on. Case in point? Jurassic Park. The first JP film specifically was a horrible adaptation of the original novel, taking out much of the science that made the book such a bestseller and making everybody OOC to the point where you can say Spielberg was practically godmodding. But the film nevertheless became a blockbuster because a) the movie itself had solid writing, pacing, and character dynamics, b) some of the changes actually made the story better instead of worse, and c) the dinosaurs look awesome. I can say with confidence that I love both the first JP movie and the original novel equally, which is something I can say for very few Movies and Sources in general.

JP is, unfortunately, a bit of an exception to the general rule, but while it shouldn't be taken as the exception that PROVES the rule, it's a good guide to how a Movie can take the original source and IMPROVE upon it rather than tarnishing it. Alas, such a phenomenon has always been extremely rare in Hollywood history, and with the drive towards experience in movies today, we'll probably never see anything even close to it for a long time. And that's terrible.

To be honest the most recent movie made off a book I've read was the Great Gatsby. The newest movie version is a terrible version of the books by the way,it misses the point of them entirely and just bored me.
Also Gatsby as Leo? Just not what I imagine him like at all,then again ever since I first read the book I headcanon Gatsby as Black so that may just be me.

My favorite of the Harry Potter movies would have to be the first two because I felt they were most faithful to the books. Which would have to be why Prisoner of Azkaban is my least favorite of the movies. So much of the Marauders got cut in favor of that stupid shrunken head—

Sorry, I should stop now before I start ranting. >:U

Oddly enough, movies that don't follow the books in anything but name can be pretty awesome stories in their own right. See How to Train Your Dragon and The Frog Princess; literally the only thing that was the same about The Frog Princess was the title. I loved those books as a kid and initially refused to see the movie because it looked like they'd butchered everything, but the movie was unrecognizable from the book and therefore I had no beloved characters to get mad over. (And I actually adore the movie as it is, so bonus points!)

Tl;dr, either be faithful to the books or make it completely unrecognizable. :P

(I haven't watched the Hobbit movies after seeing a couple things about them on-Board.)

Basically, as movies — standalone works of art — the LotR trilogy, or, at the very least, the extended three-hours-each edition, is pretty good. I don't have a lot of complaints. As adaptations, however... there are various integral things that get left out or get changed (such as Anduril being such a big deal). Adaptation Decay indeed.