What did you think he was?
My estimation of him has certainly gone up having had a closer look at him with him in England. When you look at the squad he has he's doing a fantastic job. Perhaps you could say his work in the transfer market hasn't been as good as you'd like, but then again Liverpool is not the most attractive destination at the moment (see Götze turning them down), and there are some good (Matip), or very good (Mané) signings in there with the seemingly bad ones (Klavan, Karius, Wijnaldum), and he's certainly made more progress in one summer transfer window than Wenger typically has.
But I mean, I really think people underestimate the crapness of the squad he's taken over...look at those defenders and midfielders he inherited...Moreno, Sakho, Can, etc...if you look at the players he came in to find individually he's had a positive influence on practically everyone bar Sturridge.