Well, he obviously wanted other strikers ahead of Bendtner, but he just couldn't get them. How much he's at fault for it, is tough to say really (City not selling Dzeko, Llorente being held in the Bilbao prison dungeons by Urrutia, Berbatov's wife not wanting to move from England, Jovetic costing 30 million which we don't have, etc.).
Calling for his head, though, is simply laughable. He's built us a very good squad. It just lacks the icing on the cake, a top striker.