"It's supposed to be a compelling FPS; I didn't find it compelling."
Do you really find that to be a valid criticism? That's not unlike someone saying "it's supposed to be a good game and I didn't think it was".
Perhaps you didn't find it compelling, but that might be because it didn't offer what you were looking for. If I were to play a tactical shooter (a genre which I do not personally enjoy), I wouldn't find the game compelling, regardless of how great fans of the genre might think it is. But the problem wouldn't be with the game, but that it was simply not my cup of tea.
Personally, I find Doom 3 to be the most compelling game I've played in a very long time.