When you're beached on the couch with very little to do, you start to look around, and you notice things.
Small things, like subtle indications that maybe the kids aren't really sweeping under the furniture.
Even though you've explained that not getting all of the dust bunnies just means they'll get bigger and come out from under the couch to attack!
And I don't think the problem is exclusive to the couch. I have my suspicions other areas of the house have been neglected as well.
Or maybe I just need to get over this flu and get out of the house.