Why does mages have to choose between 4 stats and other just 3

[PArcher]

Simple question and want to know what the comunity thinks. Why does mages, SCH/WMH/SMN/BLM, have to choose between PIE, DET, SS, or CRIT while melee just choose between DET, CRIT and SS. Why not add some gear for melee that dont have VIT?

Casters don't use PIE though. The only gear that can have it is crafted gear, and if you want to go that way melee can add parry to their crafted gear "just in case". There is no melee raid gear with parry, and there is no caster raid gear with PIE.

Healers fall into another category; they don't have to deal with accuracy like DPS do (and all acc on their raid gear is extra stats that don't take anything away from the more important ones).

So, considering that, the stat choice differences are:
DPS -> SS, Crit, DET, Acc
Heals -> SS, Crit, DET, PIE.

4 and 4.

EDIT: if you really want to get into it, look at tanks. Parry, Acc, DET, Crit, and SS are all important, and sometimes even PIE could be used (OK, no one uses PIE as a tank, but if a PLD wants more mana for stoneskin spam in T5, he can do it).


EDIT2: I'm also guessing you, OP, have no experience at all being a melee if you want to remove VIT from our gear. That would be the same, no, worse than removing it from yours.

[Nekodar]

WHM only have to worry about SS, DET and PIE
SCH is the one that can take advantage of Crit