Because the ruler at this line is yielding rather than firm, real command must be delegated to the one line in the hexagram capable of holding it, the firm second line. A yin stroke occupies the ruling position, a notable mismatch by the standard rule that expects firmness at this station, and the line text addresses that mismatch directly rather than concealing it. This is one of the clearer examples in the whole system of a hexagram naming its own structural imbalance and prescribing the remedy within the line text itself.
When this line changes, the central stroke of Kun becomes firm, turning the upper trigram into Kan, so that Kan now stands both above and below. The resulting hexagram is Number 29, The Abysmal, water doubled, an image of danger repeated and compounded rather than resolved. That the ruler's own weakness, if it changes without the capable hand described in the line text actually holding real authority, doubles the danger already present in the lower trigram rather than easing it, is a direct structural argument for exactly what the line insists on: command delegated to genuine capability, not asserted by right of position alone. This is one of the more direct structural warnings in the whole set of sixty four hexagrams, tying a specific delegation of authority to the avoidance of a specifically doubled danger rather than to any general moral principle.