I think it has something to do with how the character's sound. I mean, that's how I look at it. If you listen to some of the Naruto characters, like Danzo, some of them just do no sound right in English when compared to how they sound in Japanese. 

That being said, some anime are really good in English, in my opinion, like Death Note. But I can see where some people are coming from. 

It really doesn't matter with subbed or dubbed voices to me but I think some voices for dubbed anime sounds a tad bit off for some characters.  The same thing can be said for original Japanese voices like Goku from DragonBall Z.

Here is the thing.

60% of all of the worlds animated content comes from Japan (according to wikipedia). So they are BY FAR the largest animated creators in the world, and thus have the largest voice acting industry in the world. In fact, there are 130 voice-acting schools in Japan... 130! It is a very big part of their culture, and voice actors are their equivalent of "Hollywood superstars".

So Japan takes voice active very very seriously, and has a MUCH larger animation industry that any other country, this leads to extremely high competition to be voice actors (who are very well paid when voice acting a popular anime).

The voice actors attend these specialized schools where they learn how to bring their characters to life. Even the very small roles are well acted, something that I've rarely seen in English dubbed version.

A final point. The amount of time a character has to say what they need was drawn after the Japanese voice actor has red its lines. That means the English voice actor sometimes has to rush, or stall, in order to "fit" the animation. I always notice this, and it's annoying.

I've seen many many anime, and while the dubbed versions can be good, they don't have the same phenomenally high quality as the Japanese voice-actors.

Eh, matter of opinion mostly. I personally don't like it when they're just really really really really bad. Like... Early Naruto or Pokemon bad. I'm looking at you Sakura and Brock/ Ash / Misty/ Prof. Oak/ Everyone else in the first two seasons. Except James on occasion, you actually nailed it once in a while.

But really though. Sakura sounding like a full grown woman is ridiculous.

I prefer dubbed animes but I just hate it when the dub is very poor quality. :/