Lessons Learned
During wars and other operations, the troops often encounter situations for which they have not been properly trained, or are not properly equipped. In the interests of improving their warfighting capabilities, careful study is given to these problems.
The Army and the Navy call these studies "Lessons Learned", and promptly shelve them. The next time there's a war, they say things like, "Hey, here's a bunch of new 'Lessons Learned'," and promptly shelve them.
In contrast, the Marines say these studies are "Lessons Identified", and promptly shelve them. The next time there's a war, the Marines say, "Hey, we still haven't done anything about those 'Lessons Identified'," and once again shelve them.
The Air Force also terms these studies "Lessons Learned," and also promptly shelves them. The next time there's a war, USAF announces, "See, if we'd only had the F/A-22 these problems would not have arisen".
Only the Brits have the right attitude; they refer to these studies as "Mistakes we're bound to make again."