To all people saying that "Let them die" doesn't work, i invite you to read
http://en.wikipedia.org/wiki/Classical_conditioning
Also, in other words:
"Human intelligence, as distinct from the intelligence of non-human animals, results from a metasystem transition that allows the organism to control the formation of associations of mental representations, producing imagination, language, goal setting, humor, arts and sciences." as quoted from
Turchin V. (1977): The Phenomenon of Science. A cybernetic approach to human evolution, (Columbia University Press, New York).
"results from a metasystem transition that allows the organism to control the formation of associations of mental representations"
"control the formation of associations of mental representations"
"formation of associations"
Stand in fire = dead
Attack mob which doesnt have aggro on it by tank = dead
Not using class spells/abilities properly = dead
Those above are basic associations.
WoW is Not a hard game.
Simple.