John Logan's credentials were called into question by many before Nemesis was released. He was nominated for an Oscar for Gladiator, but people argued that it wasn't all him or that it was a fluke. Well he's since gone on to pen great films like the Aviator, Sweeney Todd, Rango, Hugo and the amazing Skyfall.
So what the hell went wrong with Nemesis? Too many cooks in the kitchen? Not enough cooks in the kitchen? At what point did he think he was writing something good?