I don't have very many titles from the Vertigo imprint (just Otherside and We3), but from what everyone tells me at my local shop, it seems like Vertigo can do no wrong with every title being spectacular.
I don't believe that. Vertigo must have at least one bad title. We can all name at least one bad title from Marvel, DC's other imprints, Image and all their imprints, but I have yet to hear about a bad title from Vertigo.
Note: The title must be bad across the board. Not just a single opinion, but more of unanimous call.