How the RAF & USAAF Beat the Luftwaffe

"The Luftwaffe had to be used in a decisive way in the Battle of Britain as a means of conducting total air war. Its size, technical equipment and the means at its disposal precluded the Luftwaffe from fulfilling this mission." - Adolf Galland How did the RAF beat the Luftwaffe during the Second World War? Was it actually the fact that they did not lose which later enabled them to claim victory – a victory that would have been impossible without the participation of the Americans from early 1943