Suppose one votes to close a question in "main", and the poster asks in "meta" why it was closed. Apparently the existence of that discussion in meta is not included among the "notifications" received by those who closed the question. Since it would be impolite for the latter not to respond if they knew the discussion was happening, this amounts to a bug ('bug' in the informal sense of bad design, not the technical sense of the 'bug' tag which refers to unexpected behavior).
