It’s a bit of a developers’ cliche that players will consume content faster than you imagined was reasonably possible. I bet that when the good folks at Blizzard were developing the Burning Crusade expansion for WoW they intended to create new content that would last months for your average player. Indeed, it probably does take months for your average player to get through it.

It must be annoying to then discover that someone has burned through the expansion in less than 24 hours.