On losses in action:

Admiral Sir Henry Leach, who was Britain's First Sea Lord and chief of the Defence staff during the Falklands war, once said,

"Isn't it bizarre that no one complains when the army or air force loses a tank or plane, but all hell breaks loose when a warship sinks? Warships are meant to be used—and some will be lost. But we are here to employ our forces, not languish in fear of risk or for enemy ..."

Leach was able to say that partly because he knew exactly what it costs when a warship goes down with hundreds of men.

His father, Captain John Leach, had been the captain of the Royal Navy battleship "Prince of Wales" and went down with the ship when it was sunk by Japanese aircraft in 1941. 

A similar comment from Admiral Andrew Brown Cunningham, who was the RN's Commander in Chief for the Mediterranean theatre, on the losses his ships were taking from Luftwaffe attacks while evacuating British soldiers from Crete during Word War II:

"It takes the Navy three years to build a ship. It will take three hundred years to build a new tradition. The evacuation will continue."

Of course because ships are major assets and losing them is a very serious matter which tends to involve the loss of hundreds of irreplaceable lives as well as massive costs in both military and financial terms, no well-run navy would ever encourage its' senior officers to blithely ignore risks to their ships.

No admiral or captain should ever take unnecessary risks with the safety of his ships. But it is an inevitable fact that whenever you go into battle, there will be risks.

In the age of drone warfare, those risks are even more serious. Any Defence ministry who are remotely competent should be looking at the current state of warfare - and particularly at what the Ukrainians have done to the Russian navy with drones - and thinking very hard indeed about how to defend their ships.