Actually, it is a myth, started by a creative author, and comes to us third hand.. Discussed in detail here: A Guilty Man? – Airminded.
Nothing is so good for the morale of the troops as occasionally to see a dead general. Field Marshall Slim
" We reckon it´s rough here! You can reach through the hedge and put the safety-catch on their Spandaus!" US Soldier describing the war in Normandy summer 1944
" I now consider the Reichswehr to be only a military training school for the German people. The conduct of war and therefore also the mobilization are henceforth the concerns of the SA". Ernst Röhm before his death
"Before we're through with them, the Japanese language will be spoken only in hell". Admiral Halsey December 1941
"I´ve just received 5,000 Luftwaffe pilots each with a little iron cross on their neck. tell me what shall I do with them?" Felix Steiner in Apr 1945 to von Manteuffel after getting the replacements for the tanks Cornelius Ryan "The last battle"
There are only three types of people Those who make things happen... Those who watch things happen... Those who wonder what happened. Unknown....
Theres a fourth before the first...People who decide what happens. And a fifth...People who don't care what happens.