Everyone who reads comics hates at least one character, and that's okay. Some characters just don't sit well with certain people, and - whether for a good reason or not - they end up having a weird kind of animosity towards the fictional figure. It's one of the things that keeps comics interesting, as personal preference can affect which characters end up coming back time and again, and which are killed off faster than the eye can see.
But some unfortunate comic folk ended up hated by whole swarms of people for reasons that just don't seem that fair. Through one bad writer, one bad introduction, or just missing the point of a character, some heroes and villains get flack for things that actually don't reflect the actual character, and that frankly kind of sucks.
Now, this isn't to say you can't still hate these characters - after all, there'll always be a few comic faces that drive you up the wall. But it's always worth giving them a second chance, too, if only to figure out whether you have a true dislike for them, or if you just caught them in a particular issue or two you weren't fond of.