I see so many fangasms and excitement for KHIII here but have you guys ever thought that KHIII won't be the godly game you're expecting it to be? There are several easy reasons why it could be bad so allow me to begin
As Nomura said it was announced too early. We've seen video game companies release games that had great potential early just to try to please the fans but ultimately fail. coughSonic06cough It is very possible that Square could end up releasing the game early, thus ruining it's potential.
Secondly, the story. Over 50% of those people who are excited for KHIII have not played any of the portable games. They won't understand the story at all which will lead to many persons' experience with KHIII to not be at it's full potential
"Just recap the the plot via cutscenes at the beginning" Yes. I agree. Let's have a 1 and a half hour to 2 and a half hours of opening movie to the game.
These of course, are the most obvious reasons. Let's get into some more detailed ones.
First off, fans have speculated a pixar world since the dawn of time. And now that the response to pixar worlds was "No comment" people expect that as a yes. I don't even need to explain this one.
Secondly, it's obvious, so so obvious, that not every fan will like KHIII even if none of the above reasons come to pass. Some fans will be mad if Gummi ships come back, some not. Some will be mad if the game doesn't come to Wii U later on, some will rejoice, some will be mad that Donald and Goofy are back, some will be happy. Little things will bunch together to leave some fans with an overall dislike for the game.
Finally, there's the game itself.
As we all know, Nomura has a Yoai Fetish. It's likely that the game will contain Yoai fanservice. For this reason most of those who hate Yoai will probably hate the game.
To start off, the Osaka team is making this one. Those who wanted something like KHII could be very out of luck with this one.
And lastly, the gameplay. We don't even know what the gameplay even will look like. "But. But. The trailer. It showed gameplay!!!" The trailer did not. What was seen in the trailer was just animation and not gameplay as said by, you guessed it, Nomura himself. For all we know the gameplay will look terrible.
So yes, the game can be bad and most definitely will not be near as good as you are thinking it will be. In fact, it will probably be the worst thing to ever exist in the Kingdom Hearts Universe. Just like Xion.