Why frigates strain the armor-speed-firepower diagram

Frigates are hard to place because their combat value does not map neatly onto the same axes as capital ships. Second World War frigates were not especially fast and carried no meaningful armor, but they possessed specialized anti-submarine firepower. Modern frigates extend that problem because sensors, missiles, and mission systems matter as much as traditional gun weight. The moment is useful as a warning that a simple visualization can clarify one family of tradeoffs while obscuring another.