In part this was due to the increasing pre-eminence of the other branches of the German armed forces, in particular of the "Luftwaffe". The commander in chief of the "Luftwaffe", Hitler's friend and political colleague Hermann Göring, always had personal influence with Hitler which no Army leader had. Another was the increasing tension between OKH and OKW. While the need for a joint headquarters to coordinate the work of all the services was desirable in theory, for example to determine industrial and manpower priorities and avoid duplication of effort, OKW was increasingly used as an alternate Army planning staff by Hitler. At the same time, OKW failed in its task of overseeing the overall war effort, resulting in wasteful diversion of resources to several competing and unregulated forces (such as the SS) responsible only to themselves or to Hitler alone.