Typically many nations tend to name warships after places, famous sailors, victories and the like. The Royal Navy is no different to a large degree. However she also does have another wonderful tradition of using attitudes and adjectives essentially, in no small part to imbue the ship with some measure of her name. However the RN also has a long memory when it comes to ships names, and a long list of capital ship names that had essentially become canon, with the exception of occasional additions for the sake of monarchs or additions to the Empire.

The names Erebus and Terror also lived on as well, and again in less than dominating vessels. They were a pair of monitors in WW1, small ships armed with a single 15in gun each and used to bombard coastal positions. Terror however would go on to get one later shot at life, HMS Terror was the name for the RN base in Singapore after WW2.

We can even track this trend more recently, the task force that operated off the Falklands included HMS Avenger a Frigate, HMS Fearless an Amphib, and the famous HMS Conqueror a nuclear attack submarine. While we can also track how at least one key name has transferred based on how the evolution of naval warfare has valued certain ship types.

HMS Dreadnought went from a ship of the line, to a turret ship, to Jackie Fisher's evolutionary design, to in the 1950's the UK's first nuclear submarine, to just recently it was announced as the name of the replacement for the RN's Vanguard ballistic missile submarines.

Meanwhile Queen Elizabeth went from of the finest RN battleships ever built to today the new class of RN aircraft carriers.

But to your larger point the fact is just like the USN, the RN basically has too many names for too few ships, often times the modern or current political winds dictate the name of a vessel as often as tradition. Thus many long standing and well regarded names sit idle, even ones dating back to Trafalgar like Bellerophon, Revenge, and Temeraire.