Why do people save LB till the end of the fight?

[Yeol]

Especially in like very easy trails/raids.

In dungeons too. Like why not use caster/range lb3 on a large group of mobs instead of saving it for the boss, the lb would do more damage to a large group of mobs than it would do on a single target.

For trials/raids
LB3 sometimes is used for mechanics such as tank LB3. It is also saved to be used by healers when learning the fight. Caster/Ranged LB is sometimes used if there is more than 1 target. Melee LB3 is usually used at the very end of the encounter when none of the things I mentioned before are needed.

For dungeons
Caster/Ranged LB is better used on large pulls. Melee LB can be used on bosses or single target door mobs if it's up.

Most people don't use LB in dungeons, sometimes the dungeon is cleared without ever using LB. I think the reason for this is because people are not used to seeing other people using LB while doing dungeons. If LB was frequently used in the situation I mentioned above it will be the norm and more people will remember to use it.