Why are rings unique equipped?

[BHGlobbd]

This is just something that's been bothering me, yes, I am aware that you can upgrade for the hunts, but that just delays the problem in that you can't equip two of the same ring. I don't understand why the rings are unique equipped and can't be made so we can use the same ring on both fingers.

I play DRG, I am currently using the 180 ring of Slaying and Fending. The fending ring has Determination and skill speed, 2 stats that DRGs can use. Each ring has a stat that all classes use.