I really liked the game for the first few hours, but after that it just seemed to trail off. I think the main thing about Starfox is that the objectives seem ridiculous and not 'epic' enough to bother finishing. It's polished alright - especially the graphics - but it lacks any sort of motivational spur.
Penny-Arcade put it pretty well, but I think it was said best by whoever called it 'Zelda without a soul'. (Does anyone know who that was by the way?)
I rekon that if I had plenty of spare time I would more than happily delve into the game and dutifully complete it without noticing anything amiss, but I simply don't, and I would question whether many gamers do. I have a theory that Zelda manages to avoid the boredom factor by creating such a great atmosphere, and therefore it engrosses the player to such a level that collecting fuel cells or whatever doesn't really seem to bad. As I understand it, Sphinx and the Cursed Mummy had similar problems.
Before the DS was announced, Iwata and Miyamoto did a few interviews and so forth about how Nintendo is aiming to create games than can be played in short bursts just as well as they can be played for longer periods of time. To me, Startfox represents that opposite of that philosophy. Because I feel little motivation to achieve the objectives, then they feel like a chore, and chores will always seem to take too long. There's simply little reason why things should move so slowly other than to inflate the time required to finish the game. In short, to get anying out if it, you need to put