Hokage
Kazekage
Sound Ninja
Sound Ninja
Countless children
Hokage's bodygaurds
Countless test subjects
Was reason for the death of 1000+ With Sasuke's training
Since Orochimaru himself admitted being
inferior to a 13 years old boy who put him in his place i could care less what kind of opponent he has killed as he can't possible defeat Itachi unless the guy is drained and deadly ill, oh wait, even then he couldnt last more than a second.
As for being a failure.... notice how all the best shinobis keep claiming they are failures :
Hashirama, Hiruzen, Minato, Itachi...
It's called being modest and wise and hard on theirselves. Despite everythnig he has done, Minato still considers himself a failure because he couldnt protect Obito, Rin and Kakashi. Despite saving the alliance twice, he says it's still doesnt make up for all that he failed.
Itachi says he his a failure because he doesnt have a perfect score on his sheet, yet that doesnt make him a failure and everybody knows this. The irony lies in the fact that right now, the alliance is still standing because Itachi was able to have an impact on Sasuke, thus lead to the revival of the former hokages.
Now some may say it was because of Kabuto that he was there and he was lucky because he got hit by Kotoamatsukami, While this is all true, it still doesnt change the fact that it's exactly because Itachi plans for everything that shit did not hit the fan.
Either Kotomatsukami was going to be used on him (which happened), or it would have hit Sasuke with it, thus putting Sasuke on the alliance's side in the end.
Itachi being a failure... yeah right. Stop repeating his words because thats actually the only negative thing u can find about him. Even Kabuto was getting annoyed by Itachi repeating that he was a failure.