Why Crit for tanks?

[Mikey_R]

I remember old raiding gear not having materia slots. Only crafted gear could be melded, which made it really annoying trying to hit those accuracy thresholds as you had to use lower ilvl pieces. Not only that, but harder content required a lot more accuracy, so you either had to swap pieces or just go in with wasted stats when doing older content.

This was so inconvenient for healers that SE had to start putting bonus accuracy on their gear. This is why a lot of late ARR healing gear has direct hit as a third stat on it.

Materia slots were added part way through HW, though I don't remember exactly when.

Tanks also had it rough. Enemies had different accuracy requirements based on where you attack the boss, rear had a lower accuracy requirement compared to flank, then front had it even higher. Since tanks had to account for being infront of the boss, more gear/materia had to be dedicated to accuracy. They tried to alleviate this by adding increased accuracy on tank stance (+5% IIRC), but since everyone was tanking without tank stance, it didn't make a difference.

[Absurdity]

Personally, I miss the days of accuracy thresholds. It forced players to actually think about substats and making certain gear choices while working towards BiS. Missing an ability and doing 0 damage (and possibly breaking a combo) made accuracy THE #1 stat up to a point. Then it was useless. However, it made gear selection more interesting. However, I think SE realized players don't want to put that much thought into gear.

It was not just accuracy, it was also vitality.
Back when tanks could use dps accessories, and those had no vit on them, you had to figure out how much health you needed (or how little you could get away with) for a fight to comfortably do your main job, not dying to tank mechanics, while putting as much into more damage as possible.

It wasn't super interesting either, but it added a few more considerations to "stack as much crit as possible".