Sometimes when I go to a friend's house, they have dishes in their sink that have obviously been there for a number of days. Conversely, I have had roommates who will cook a complex meal, dirtying many dishes in the process, but still have very little cleanup after the meal because they clean efficiently as they go (a practice I try to emulate to varying success). I would say the former group is not very good at washing up their dishes, while the latter is (from my own observations, at least) better than average.

edit: this is also one of the easier questions to actually have a good sense of where you stand. I don't know how often most of my peers cry, for instance, but I do know how often I visit someone's house and they have dirty dishes lying around, or they leave dishes from a dinner party or get-together in the sink for the next morning, etc.