Reasons:{I'm in a ranting mood, forgive me:P}
Nathan: I really liked him in seasons 1&2. I thought his bad boy side in season 1 was really fun and interesting to watch and I liked seeing how he slowly started changing as he dated Haley. Season 2 was my favorite season of his, I liked how he was vulnerable and in love and how heartbroken he was when Haley left. We got to see a perfect mix of the old Nathan and the new Nathan. But after the first two seasons I feel like his character became very boring and repetitive and had the same storylines. I still like him, but not nearly as much as the first two seasons.
Serena: I used to really like Serena's character in season 1, which is a shocker considering she's my second least favorite character now. I just feel like her character got very bitchy, whiny, and annoying as the show went on. I hated how Serena could do and say anything and would get almost no consequences but if any other character did half the crap she pulled they would get so much shit on the show. I also hated how she never fought any of her battles, and always had her friends fight them for her. I just really don't like herXD:p
Chuck: I really liked Chuck when Gossip Girl first started but his character slowly started to get really boring and when he "sold" Blair to Jack for his hotel, that was pretty much the final straw for me. I hated how they turned him into this obsessed person.
Rory:I feel like after she left high school she turned into this whiny and selfish person. Rory used to be this really cool kid with an amazing personality that was always there for the people she loved. Then she started throwing temper tantrums, crashing yachts, sleeping with married men, etc etc. I still like her as a character, but not as much when the show first started.
Silver:Season 1 Silver was amazing and could possibly have been one of my favorite characters ever if they kept her the same. I liked how she was different and had her own thoughts and style. I loved how she always stood up for what she believed in and how she dealt with her bipolar disorder. But after season 2 she just became like all the other characters and started doing things she would have never done. I still liked her, but she doesn't even come close to the epicenes she was in season 1.
Adrianna: I feel like after season 1 she became boring and then when she became famous her character just became horrible. I hate the way she treated her friends and got involved in drugs. And I know she had a reason to hate Silver, but I think sending naked pictures of her to everyone and messing with her medicine was taking it way too far. So after season 1 I definitely had a like-hate thing going on with Adrianna.
Alex:I thought her character became annoying after she temporarily left Nikita. Once again I understand where she was coming form, somewhat. But Nikita was always there for her, taking care of her and guiding her and I just hate the way she treated her. Plus, her character started becoming a bit boring as well. I still like her, but she was definitely at her best in season 1!
Aria: The main reason I don't like Aria as much as I did in season 1 is because of her lack of involvement in A. I feel like all the other girls are tortured by A so much and that their lives are in a complete mess because of A, where Aria is just kind of there in her own little Ezra world. Aria doesn't seem to care about A at all and only seems interested in Ezra which always bothered me.
Fez: I liked how when 70's first started Fez was funny, goofy, and the naive one that the gang used to look after and mess with. But then as the show went on his character became really pervy and disgusting. And the jokes and things he started to do where no longer funny just disturbing. So I definitely didn't like his character as much as I did when the show first started.
Miranda: I loved Miranda in the first 5 seasons of GA! She was in my top 3. She was bad ass, funny, always looking out for her interns, and I looked up to her, but as the show went on I felt like her character started becoming really annoying and judgmental. And they started softening her up which loses the essence of who her character really is. I still like her I just miss her Nazi days where she used to always have tabs on MAGIC.
Daniel: I loved Daniel in season 1. I liked how despite being a Grayson he was still caring, nice, and just an overall great guy who obviously had his flaws. But {from what I've seen of season 2 so far} his character just became like the rest of the Grayson's and it's honestly pretty irritating, because I liked how at first he was different from them and wanted to have his own identity but then they just ended up making him exactly like his family.
Zoe: I feel like Zoe's character became very inconsiderate and selfish after she broke up with Wade. I just felt like she started messing with everyone else's lives and became very whiny. Hopefully that changes in season 3 and she goes back to her old self.
Julian: I liked how in season 6 he was this cocky, bad ass guy, but still had this dorky, nice side to him. He was funny and nice. But in seasons 7-9 {from what I saw} I thought the turned him into too much of a dork and sissy because they needed comic relief. I mean he had an entire conversation with Brooke in season 6 about how he was no longer the way he was in hs and that's exactly how they showed him later on in the show. Super annoying and it definitely made me hate his character.
Phoebe: I thought she just became annoying and selfish after season 4. I didn't like her storyline with Cole and I didn't like how she became obsessed with finding a husband and getting a child. She started constantly using magic for personal gain and it was all just too much and definitely not like her character.

I completely agree about Aria...she lives in Dawson's Creek!!! and she talks so much about how miserable her life is because she can't be with Ezra! ugh!!

She is always like..."Stop being so whiny girls...I know that Maya died and Caleb got shot and Toby is A but it's not a big deal, it's not like any of them has a kid...THAT IS SERIOUS SHIT BITCHES!!"

it annoys so much!!

Also agree about Nathan!!

Moosh how dare you put Chuck Bass on that list!! Ale judges you!!

Completely agree with Serena. I loved her in season 1, she was even my favorite but after that she totally became annoying and bitchy !

Usually, when I start loving a character, I keep continuing to love them no matter what the 'cause because I'm stubborn. LOL

I agree ONLY with Phoebe! In fact I started disliking her after season 3 :S

& Daniel. I kinda agree on Zoe too :)