Joined Jan 2010
12,635 Posts | 4,362+
UK
Hong Kong, Malaya, and Burma proved impossible to defend, consumed precious resources, and ultimately contributed little to Britain's war effort. Just trying to defend Singapore cost Britain (and the CW) three divisions and two battleships.
William Slim proved Burma and Malays weren't impossible to defend. It was just poorly managed until he took over. It was mostly an administrative issue, and once he put the house in order, the potential and ability of the troops shone through.