User blog comment:Zathronas/Analysis by an author: Dust secrets/@comment-10380701-20140823014951/@comment-10380701-20140823015808

Hm. Well, time to got at this again.

Fire, Water, Lightning and Wind have something in common and that's the fact that they can easily come from nothing and return to nothing in a short span of time. (Longer for water, but still)

Meanwhile, Earth is solid and firm. If say, a million Earth Dust users decided to troll Remnant, they can make a mountain of rocks easily by manipulation of the earth. And that won't go away.

Fire burns out, Water dries away, Lightning dissipates, Wind moves.