Favourite warships that never reached the fleet

Which never-built warships stand out as favourites?

The favourites include the Malta class, USS United States, British and Dutch battlecruisers, Francesco Caracciolo, and the Russian Borodinos.

The list ranges across carrier, battlecruiser, and battleship projects rather than selecting one technical winner. The Malta class and the large American carrier United States represent competing postwar aviation ideas. British and Dutch battlecruiser proposals, Italy's Francesco Caracciolo, and the Russian Borodino-class battlecruisers preserve other abandoned design trajectories. These names open several routes into how finance, treaties, and changing requirements leave important ships on paper.