1. Hitler had deluded himself into believing that GB would eventually see 'the error of their ways' and join him in his crusade against the USSR. When they instead opposed his plans, he had prepared no plan to conquer GB, and was thus caught unprepared for the Battle For Britain.
2. While Nazi incompetence is a major causitory factor in Britains win, one cannot deny the bravery of the RAF and the British people in fighting what appeared to everyone in the world to be a lost cause.
3. The failure of the Luftwaffe in the Battle For Britain was not a case of Goerings incompetence, but an early example of Hitler adversely interfering in operational tactics to scratch an emotional itch. Goering, with his superior air force, had been pursuing the right strategy, targeting the RADAR installations, RAF airfields, and airplane manufacturing plants. This was having measurable effect, and, had it been continued, could have been expected to fatally reduce the operational effectiveness of the RAFs defenses. After a few British bombers "strayed off course" and dropped some ineffectual bombs on German civilian areas, Hitler ordered Goering to bomb London, thus giving the RAF the breathing room they desperately needed to repair the airfields and RADAR units and continue the maximum production of aircraft. Without this shift in tactics, the air battle, a close thing as it was, tilted marginally in Britains favor.
4. Even before Germany had lost most of its destroyers to the Royal Navy while taking Norway, it was never planned that the Kriegsmarine would have anything more than a marginal role in protecting German troops during a cross-Channel operation. This was envisioned in the last-minute, seat-of-the-pants planning for Sealion as the Luftwaffes responsibility. One cannot blame the Kriegsmarine for a lack of troop transports because they had never been instructed to acquire them. Hitler never suspected that Britain would force the issue to such an extreme. No serious planning for such an invasion was ever made before the surrender of France, and the last-minute planning was indeed amateurish. Considering Germanys limited ship building potential, it is unreasonable that they could be expected to suddenly have the equipment and resources to support such an unforeseen mission.
5. The only viable conclusion one can draw from 3 and 4 is that neither the Luftwaffe nor the Kriegsmarine can be faulted for not being prepared. Both services were well prepared to carry out the missions they had readied for. It was Hitlers political miscalculations that made the unexpected necessity of a cross-Channel invasion desirable, something the Kriegsmarine was never ordered to prepare for before the surrender on the Continent. And it was Hitler's interference in the Luftwaffe offensive that caused the failure to gain air supremacy. In the event, Goerings Luftwaffe almost managed it, despite the fact that owning the air over the Channel had not been its original mission.
The sensible conclusion is that the Luftwaffe and Kriegsmarine became scapegoats for their Fuehrers incompetent political projections and counterproductive battlefield interference. Goering and Raeder should not be made responsible for Hitlers bumbling incompetence. It was, in the end, Hitler's fight to lose, and he did, indeed, cause the loss single-handedly.
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