It's pretty incredible.
I genuinely loved this game from chapters 1-4. Bravely Default wasn't initially spinning the most riveting of tales, but the world was interesting enough and I came to like the characters, despite Tiz's obsession with Agnès and Ringabel's obsession with the ladies. I actually didn't have much of a problem with the English voice acting, with the big exception being Airy (part of why I hated her from the outset).
For everything else: the music is awesome, I really liked the job system and the battle system and acquiring new asterisks from side quests was fun because of the unique bosses that held them and how they filled in the game's story and world.
But then chapter 5 happened. Awakening the four crystals didn't end up saving the world, but sends the heroes into a parallel world, which is alright in itself. But how the game decides to handle this is by recycling a bunch of scenes that happened previously in the game, with side quests which literally involve fighting the same bosses that one fights in the previous chapters, but sometimes with different story bits accompanying them in some kind of boss rush. These side quests are not mandatory to continue the story (thank god), but I still did them all anyways because I didn't want to miss any potentially important parts of the story or be confused concerning what came next.
In any case, chapter 5 is about awakening the four crystals again because that didn't save the world last time, so it must save the world this time, right? WRONG. After going through all four of the dungeons again and facing the bosses that come from the four crystals and then awakening these crystals, the team shifts into yet another parallel world and into chapter 6. The team's reaction? "Well, that didn't work, so I guess we should go awakening the four crystals AGAIN."
So, chapter 6 goes underway and the side quests of chapter 5 are back again, which means one can subject themselves to practically the exact same bosses again if they so choose. Oh, and did I mention that these side quest bosses, starting from chapter 5, usually don't give out any cash or experience points when defeated? Well, that's what happens; they only give out "job points" which is useful, but not useful enough to justify going through them all again unless one really needs to see the 1-2 lines of dialogue that have maybe changed in these side quests.
"Screw it", I tell myself after doing one of the side quests and realizing it's the exact same thing. On another player's recommendation, I do at least one of the new side quests introduced in chapter 6, which was at least a bit refreshing since it involved all new story segments and an entirely new boss. Other than that, though, I decide to rush my way through to awaken all the four crystals again, ignoring the side quests in the process.
Guess what happens after chapter 6's crystals are awakened? Is the world saved? Haha, no.
The team wakes up in another parallel world. Again. Airy, the fairy who's been pushing for the team to awaken the crystals the most throughout the whole game, gives the EXACT same excuse she's given before: "I don't know what happened. I'm sorry." So, logically, the team goes: "Well, guess we should go awaken the crystals again." ...NO, WHY!?
Same side quests are back, but to the game's credit, the encounters are at least a bit different than the previous chapters with different bosses teaming up with each other, with different motivations and story segments, making for a different kind of challenge. Not enough for me to do more than 2-3, though.
So I go awakening the crystals again, and after that's done...
Team wakes up in parallel world. Airy goes: "I don't know what happened. I'm sorry." Team goes: "Well, guess we should go awaken the crystals again."
*Sigh* I'm on this chapter now, and at least I believe this one's the final one. Side quests are back; not doing any of those. Out of rebellion, I decided to break the first crystal I reached instead of awakening it, which led me to what I think is a "good ending" but not the "true ending" (which, to get, requires awakening all four of the crystals again... again. Again.)
This is a prefect example of a game that fucks up the more it goes on. Why force the player to go through one hundred cycles like this? The game was plenty long (about 30-40 hours) at the end of chapter 4, so why pad it out like this?
What makes it even worse is that, as the parallel worlds go on and on, new story bits start to pop up that make the characters question the origin of the crystals and, particularly, their fairy companion, which makes for one of the coolest parts of the game which is how choice words on the title screen turn red and disappear after a scene:
Still, they choose to go on awakening the crystals over and over and over again, and it's the epitome of rote. If that's how they wanted to tell the story, then fine. But it's practically an insult to the player to literally recycle past scenes from the game as well as side quests and... well, everything else, just to pad out their adventure. It's dumb, and it made one of the coolest JRPGs I've played into one of the most frustrating.