"Why multibox?" -- that's the question I keep getting. Let me tell you why. In my case it's 10 characters at the same time. 10 characters have more DPS than one -- no, really! Also, being able to solo raids, instances, heroics etc isn't all that bad. Or for pvp, 10 Warlocks means 60 dots on one target at the same time as having 20 pets, 10x wild imps swarm at the same time as chain-fear. Or how about playing Death Knights on the Broken Shore, with all the rares, Sentinax- and Unstable Portals.

Having 10 characters also means 10x chance of pets and mounts to drop on EVERY SINGLE KILL, on mobs/bosses/rares that has something in their loot table.

In Legion, I made millions of gold a day if I farmed properly. This is 2 hours of farming:

.. So why multibox? Because I can! ;D