First we have this post by Adam Martin, former CTO of NCsoft Europe, where he explains his views on why the game failed. Granted, he admits he wasn't actually on the TR team, but he was privy to the internal mailing lists and information about the game from Alpha to launch. As a response, we have a post from Scott Jennings, who sums it all up fairly well with this statement: "The biggest failing, though, was that it was in development about twice as long and spent twice as much as it had any right to. And that's what promotes it, in this snarky outside blogger's view, from understandable failure to extinction-level company-slaying train wreck."
Update: Although Adam Martin's post states that he was the European CTO at the time, we get word from NCsoft that he was never the CTO for NCsoft Europe. He was the Lead Programmer.