Except when we try and reinvent the wheel that works and spend the next umpteen years trying to convince ourselves it was always the wrong answer when our wheel doesn't work.Rather than "what did we put on the last ship? Do the same for this ship..." for the close-range battery, there was actual analysis and evaluation of "what does it need to do? Which candidates achieve that best?"
See the very sensible lessons learned at the end of WWII, best small gun, 40mm Bofors, best medium gun calibre, 3", for Frigates and smaller and secondary armament on bigger ships, best big boys gun calibre, 5", for Destroyers - All ahead full! standardise on these three calibres!
Now we couldn't muck up the Bofors, so it carried on
But the 3" ? Well, we spent an age and them some trying to develop our own 3" and 5" mounts, and when we made a total horlicks of it and couldn't get them to work, rather than say 'OK, buy ones that work off someone else', we threw both calibre's on the scrapheap and convinced ourselves sticking with the 4.5" for everything was mega and everyone else was silly. So we had generations of Frigates with too much gun, and Destroyers with not enough gun.
Now back to the Bofors, the answer on the day was to move on to the automatic Bofors in the 70's, the DARDO fast 40 was giving people a bit of a stiffy, but no! Guns are so last century, its going to be an all missile navy! Enter Falklands stage left, sure enough, as we knew a decade earlier, a mandraulic Bofors wasn't optimal for shooting at jets, so, back to the automatic Bofors? Nah, buy a 30mm mount and be really different.
And here we are, 75 years on, still trying to find anything but what we, and everyone else came up with, is the right answer.
Finally get the automatic 40mm…
But perversely decide on a very short ranged 57mm that gives little extra over the 40mm, but is nothing like as good as the not much bigger or expensive and hugely popular 76mm for duffing things up, (if only the Iranians, the current threat de jour would get with the programme and stop fitting their patrol boats with a 76mm eh? How do we 'intimidate' an Iranian patrol boat fitted with a bigger gun?)
And having finally bought the US 5" we wanted all along since 1942, now decide its only going on an ASW Frigate and our AAW Destroyers and GP frigates wont get it.
The Royal Navy - always trying not to buy the guns it actually wants