Blizzard Entertainment is working to balance the number of players in World of Warcraft's two factions for high-end raid dungeons and the game's voluntary player-vs.-player War Mode. While players overall are balanced, those taking advantage of the game's War Mode (where players can voluntarily engage in open-world PvP combat) and players in end-game large-group raid dungeons skew Horde. War Mode and participation in War Mode is one thing where I think we've actually made some technical improvements to improve shard balancing in practice in [the Battle for Azeroth expansion]. Hazzikostas said said Blizzard suspects many Alliance players had "rough experiences early on and opted out" of War Mode, and the increased rewards may bring people back in. A variety of difficult-to-control factors can contribute to imbalance in populations of Horde versus Alliance in the same server areas in War Mode.

Source: Forbes November 07, 2018 14:51 UTC