The Ratio

An occasional term used to describe the overwhelming Alliance advantage of numbers over Horde on the vast majority of WoW servers, which frequently surpasses 2:1.

Many causes have been theorised for this problem, from the logically plausible (players feel more comfortable playing human-like characters), to the unfathomably silly (the Alliance has usable chairs).

Whatever the cause, this Ratio frequently causes an effect in PvP known as "The Zerg", in which Alliance forces gather into a numerically superior mob and overwhelm the defenses of a single site.

However, in the battlegrounds it has the opposite effect such that wait queues for Alliance are so long that it is much harder for regular and practiced groups to get in, so the Horde tends to be more consistent and organized.