The myth that "the best German fighter pilots were lost during the Battle of Britain" is just that, a myth.

When the Battle of Britain commenced only two German pilots (Bf 109) were Experten (aces) with a Knight's Cross: Moelders and Balthasar, both survived the battle.

During the BoB, another 21 Bf 109 and 5 Bf 110 pilots were recognized as Experten and received the Knight's Cross.

Of these 28 'Experten', 3 were lost during the Battle (July-Oct), This means that the great majority of these 'Experten' (89%) survived.

After the BoB officially ended on 31 Oct 1940 and until 31 Dec 1940, another 6 Bf 109 and 2 Bf 110 pilots became Experten. All of them survived the battles over England that year.

Of 100 pilots lost by JG51 between July 1940 and June 1941 (before departure to the East), 51 were scoreless, 35 had less than 5 victories, and only 14 were aces (14%).

These statistics were similar in FC during the battle.
Later, the USAAF also found that the losses in the air were concentrated in the less skilled or less experienced.