Why cheap escorts do not justify a compromised battleship

Navies often build economical ships, so why object to a less capable battleship such as the Revenge class?

Cheap mass escorts can create useful numbers, but a handful of capital ships must each deliver the full capability their battle-line role requires.

Ships bought by the dozen solve a different problem from capital ships built only in handfuls. A Type 31 frigate or Flower-class corvette can rationally emphasize affordability because fleet value comes from fielding many hulls for escort work. A battleship is expected to anchor the battle line and cannot rely on numbers to cover a deliberate capability gap. Procurement should therefore accept economical escorts where quantity is the requirement while demanding the strongest practical design from each rare capital ship.