User blog comment:StagedDom19/Missing the Main Problem/@comment-5124348-20120710142656/@comment-2256917-20120710193048

If I recall correctly, Vega speaks of another Collector ship and of destroying it (either to you, or to Garrus)--doesn't he? Not that it's that important, but it meant that the Collector's had more than one ship (responding to an earlier comment abou thow they had only one ship). In other words, they are speaking about doing things about/against the Collectors while Shepard, too, was doing such things.

Not that it matters, I said: because the Collectors, in order to "hit earth" (as your squadmate's say on the Collector Ship), only need one ship, one powerful, sophisticaed ship that can sneak up on or otherwise bypass defenses, land at (say) NYC, unleash the swarm, collect, move on.