It looks to be a bug with BZ.
For example, turn off all your addons, and then:
open the Achievement window, go to Dungeon & Raids -> Cataclysm Raid, and find Aberrant Behavior, click on it. For me, I will get below error:
Code:
5x ...ns\Blizzard_AchievementUI\Blizzard_AchievementUI-1.0.lua:1826: GetAchievementCriteriaInfo(achievementID, criteriaIndex [,countHidden]), criteria not found
[C]: in function `GetAchievementCriteriaInfo'
...ns\Blizzard_AchievementUI\Blizzard_AchievementUI-1.0.lua:1826: in function `AchievementObjectives_DisplayCriteria'
...ns\Blizzard_AchievementUI\Blizzard_AchievementUI-1.0.lua:1448: in function `AchievementButton_DisplayObjectives'
...ns\Blizzard_AchievementUI\Blizzard_AchievementUI-1.0.lua:1372: in function `AchievementButton_DisplayAchievement'
...ns\Blizzard_AchievementUI\Blizzard_AchievementUI-1.0.lua:1233: in function `AchievementButton_OnClick'
[string "*:OnClick"]:2: in function <[string "*:OnClick"]:1>
Locals:
(*temporary) = 5310
(*temporary) = 1