Is limit break not a thing?

[Sinh119]

It's not mentioned anywhere specifically in early content, or rather, it's not emphasized clearly enough for it to stick. Most people turn off the tutorial tooltips instantly, and any mention of LB is fleeting and un-impactful. I could very easily understand if new players have an apprehension to its use, and I assume the players you are running into are new as you specifically mention leveling and duty finder. There's that judgmental aspect that would make new players anxious, such as "Am I supposed to use it right now?" "Will they be angry at me if I use it?" "Will I look stupid?" etc... essentially a fear of failure. There's also that conservative mindset that people have where they save their most impactful abilities for the "right" situation, sometimes indefinitely (Happens a lot for damage CDs for new players as well). Regardless of what the case may be, the Limit Break mechanic is poorly explained in-game, and that's probably why you won't see it used very often in casual content, especially content that is dense with newer players.

[ShadowHunterrX]

Hasnt not much to do with new players. It's most of the time just lazyness by some peoples part -> Somebody else will do it. Still happens at lv70. And some wait for the Tank to scream LB, which isnt a good idea at all. I saw many many many deads because of the last option, bec of some fight 1 shot 1 kill mechs.

As a melee myself I use it right away at the boss when it's full. But only if the party is good or else you have a wasted LB + wipe.