They are called perfect/complete because it is not allowed to have discrepancy or any deficiency in Allaah's words, as there is in the speech of humans'.
and...
quote:
It reached me that [Imam] Ahmad used this hadeeth as proof that the Qur`an is not created.
Subhanak Allaahuma wa bihamdika ash-hadu anlaa illaaha illa anta astaghfiruka wa atubu ilayk
If I said anything correct, then it is from Allaah (subhanahu wa taa'ala), and if I erred, then that is from me and shaytan.