Remakes are, for the most part, an AWFUL idea.
Some of them:
1. 12 Angry Men. I don't have any idea why they really felt the need to make Juror #10 a member of the Nation of Islam. I know black people can be racist too, but come on, that defeats the whole purpose. The accused kid was supposed to be black!
2. The Karate Kid. It was just a half-assed attempt to get Will Smith's son to star in a movie. Jaden Smith's character learns kung-fu (that's right, NOT karate) in a few days and does it perfectly. His character seemed like a jerk, unlike Daniel in the original. The kids were too young to be fighting over a girl like that. The original had hormonal teenagers, while the remake had prepubescent kids. I admit they do make a more menacing bully - now he's a genuinely evil bully instead of a severely misguided bully. But they made the evil sensei less menacing. Kreese was a guy to be feared - even Johnny was afraid of him. Not to mention the love interest is even more shallow than Ali in the original. Ali could call out Johnny's behavior, but Meiying was like a punching bag. And where was the iconic "sweep the leg" line? (I've written fanfiction for the original. It's mostly centered around Johnny.)
3. Charlie and the Chocolate Factory. I don't know if this one counts since it was based on a book, but I'll put it here anyway. On the plus side, it did get a lot of stuff right that the first one didn't (such as using squirrels and only having songs where they belong instead of all the time), but what really puts it on the list was the Freudian backstory that they gave Willy Wonka. Do you really need to give him daddy issues? And why did you need to make him some kind of reverse Michael Jackson when it came to children? The whole point of the story was to show Charlie being a good kid as opposed to say, Veruca or Mike or the other brats. It wasn't about daddy issues.
4. Any remake where they feel the need to make it "politically correct". Did you see the Wurthering Heights where Heathcliff got a race lift?
I can understand wanting to update a movie to change with the times. I mean, the original Karate Kid, even though it's a good movie, is kind of dated. A lot of the elements suggest that (such as the girls' hairstyles and the bad guys being blond pretty boy jerks, a staple of 80s teen movies).