Why an export I3 might carry fewer guns

Why would Britain build a Spanish I3-derived battleship with nine 16-inch guns rather than the original battery?

Because it is an export design: the customer's requirement and the shipbuilder's sales case can outweigh Royal Navy preferences.

The question concerns a fictional Spanish premium battleship based on the I3 design and fitted with nine 16-inch guns. The panel treats its smaller battery as a plausible export choice: a British yard would build the armament its customer ordered. Vickers salesmanship could also influence that order. The example illustrates how foreign customers' requirements can produce a different ship from one intended for the Royal Navy.