R’ Pinchos Horowitz zt”l (Hafla’ah) said:
"Rashi cites the words “'ה' אלקי אבותכם יסף עליכם ככם אלף פעמים ויברך אתכם' and explains that Moshe said, ‘These 1000 blessings are mine; Hashem will bless you as He promised.’ What is the meaning of this? Two times in history, Hashem was ready to wipe out Bnei Yisroel - the Eigel and the Meraglim - and He promised Moshe, ‘I will make from you a great nation.’ Since ‘Middah Tova Meruba M’Puraneus’ - good is always at least 500 times stronger than evil (סוטה יא), Moshe said the blessing of 'אלף פעמים' - 1000 times, is mine as I was promised to be a great nation twice. Bnei Yisroel will get different berachos.”
A Wise Man would say: “Good judgment comes from experience, and experience comes from bad judgment.”