This was brought to mind by a similar question from @Chuck. In any case, I heard mine elsewhere and cannot vouch for its veracity, just thought it would be cool to share:
During WW2, the British forces realised that their a large portion of soldiers were dying from severe head injuries such as bullet wounds, blunt trauma, etc. Determined to better protect their soldiers, engineers were tasked to build better, stronger helmets.
Soon after the new helmets were rolled out, the generals in charge took another look at their casualty statistics, and saw that the number of reported head injuries had actually gone up!
Strangely enough, instead of firing the engineers involved, they were actually praised for a job well done (and maybe given extra tea rations, it was the British Army after all). Why this strange reaction?