In the Belfast City Hall debate on flags, there are roughly five possible outcomes: the Union flag flies all year; it flies on designated days; it flies with the tricolour; no flag flies; a civic flag flies.
Given the breakdown of the council, with 24 nationalist, 21 unionist and six Alliance councillors, it's predictable that none of them will get what they want.
The rational way is to try and find a consensual result where, perhaps, nobody will get what they want, but they won't get what they definitely don't want.
This is easily achieved by the preferendum. Each councillor gives five votes to their preferred option and one to their least-preferred. The option that wins most votes is the one around which most consensus is found.