Cockroaches!
Matt IMHO I don't think for a single instant, dishwashers are prone to attract these insects. I live in a community of some 20.000 people, in ten blocks of six towers each and 15 floors high. It's like a sort of park with little ways and big trees. Unfortunately it's 40 y/o and it has a permanent cockroach problem BUT in my flat I vacuum everyday sometimes twice, since I have a German Shepperd which is always shedding hair. Besides that, I drop 2 naphtalin balls in the dustbag of my machines. SO I don't have cockroaches at home. I'm not the Mr Knows-everything, this is just my experience. Besides, dishwashers, as you know, are almost hermetic, or else you have a problem of flood in the kitchen. So they (cockroaches) come from outside through open windows, sewage pipes, under doors and ducts, like bathroom, and elevators (or lifts). My twopence. Hugs Gus