Most importantly, why you're not using them correctly.
If you have:
- never used a melee LB on the first/second boss of a dungeon
- never used a caster/ranged LB on a large pack of mobs in the early parts of a dungeon
- saved a LB the whole way through a dungeon and then used it on the last 5% of the final boss
...then bad news, you're wasting time and damage.
In my seven years in this game, I've heard some incredible "reasons" for not using the Limit Break at a reasonable time during a dungeon.
"If you use it at 5% or lower it does more damage"
"If you kill the final boss with it, you get more EXP"
Those are genuine explanations I've been given for not using the Limit Break.
What's worse are the stories of people getting shouted at, belittled, and even kicked from the duty for using the Limit Break correctly - most likely because the rest of the party are the kind of idiots who I mentioned above. That is just disgusting behaviour, and if you've been involved in that kind of abuse of the kick system, you should be ashamed of yourself.
There is literally no reason at all to not use a Limit Break as soon as reasonably possible. It is a massive amount of damage that is beneficial to the party as a whole, as enemies die faster, which means less healing, which means everyone moves on faster. Unlike some AoEs, they don't have damage drop-off either.
Here is a table showing the potencies of all Limit Breaks. For example, the level 1 LB for a caster does 1650 potency to every enemy it hits in one go. Sure, the whole thing takes around 7 seconds from hitting it to regaining control of your character, but unless you can show me how you can match this ridiculous potency in the same 7 seconds, you should be using it. The fact the potency increases to absurd amounts after that, capping at 9000 potency for a level 3 melee LB, just further screams "USE ME!"
"But what if the healer needs to use it?" I hear you cry. My friend, if you need a healer LB to save you, you have MUCH bigger problems to take care of.
So please. Start using the Limit Break appropriately, to the benefit of your party.
If not, then I hope that the tanks and healers reading this will follow my suit and deliberately spaff the Limit Break up the wall at the start of the last boss, because people need to learn.
Thanks for coming to my Ted Talk.