A couple shares a bedroom. The husband has Gua 1 (Kan, East Group), the wife has Gua 8 (Gen, West Group). Their auspicious directions are different, which is common. The husband's Tian Yi (health) is East. The wife's Tian Yi is Southwest. They cannot both point their heads toward their own Tian Yi in the same bed.
The room layout: the door is on the North wall. The only solid wall without a window is the East wall. The South wall has a large window. The West wall has a closet.
The decision process: first, the position rules. The bed goes against the East wall (the only solid, windowless wall), which naturally points the head West. That is not the husband's Tian Yi (East) or the wife's Tian Yi (Southwest). But West is a neutral direction for both — not one of their four unfavourable directions. The couple checks: West is in the husband's unfavourable directions? No. West is in the wife's unfavourable directions? No. Good — it is neutral for both.
They prioritise the position rules over the direction rules. The result: solid headboard against a solid wall, clear view of the door from the bed, no window above the bed, and a neutral direction rather than either person's ideal. Both sleep well. The couple's compromise is not a failure of Eight Mansions — it is the correct application of Eight Mansions, which is a tool for optimisation within real constraints.