Clearly wrika since Mirror's Edge, Far Cry 2, Fallout, and Banjo aren't on the top 10 THEY ARE ALL BOMBS
Expectations.
Far Cry 2 wasn't set to put the world on fire. I don't see it as a bomba, as it wasn't exactly a high profile release.
EA did said they expected Mirrors Edge to sell 3 million copies though, and it seems they have changed their tune about it a bit. So it might not be a bomba, i mean expecting 3 million across 2 platforms, and by the looks of it, not coming close, isn't exactly good news but it's not like it was hyped to high heaven sales wise by the "industry".
Fallout, well, supposedly this was going to be huge, it was gonna really be selling like hotcakes, and apparently it isn't, so while it ain't a bomba, i don't think it's doing as good as some thought.
Banjo, well, MS kinda passed this under the rug, 40$, meh release hype. I don't see success slapped on its forehead, but expectations seemed low.
Again, you aren't really reaching a point. If gears of war 1 had launched to the sales numbers of LBP, and gotten a 2nd month like LBP, it would be considered a bomb, in relation to the hype, be it fan based, publisher based, journalistic based, be it on the marketing presence it had.
So fuck yes, when those factors are taken into account LBP bombed. It didn't launch in a vacuum, expectations were created by various factors, and try to dismiss those, and trying to look at it in isolation doesn't work.