Belt Charm Slots - why randomise the slots?

Unless i'm missing something entirely here, which happens enough in my old age, why do iLvl belts beyond whatever the min character levels are to equip / use 3 slots, roll with a randomised range?

Is this j ust another way to make 66% os belt drops instantly useless?

Or is there a genuine reason to not want 3 at some point?

To waste your time/add value to some of the white bases compared to others.

Hey this is weird. @Moderators. How did two of these threads get posted? Can delete one please? OR not.