The most favorable opportunity for an invasion is judged to have been immediately after the fall of France, while Britain was still reorganizing. As time passed, Britain produced more equipment and reformed its units. Training became more settled, and troops occupied prepared positions with pillboxes and other fieldworks. German preparations also improved, but an attacking force needed a decisive firepower advantage over the growing defenses.
Notable Point · 25:58-26:56
Why delay strengthened Britain's defenses
Delay gave Britain more equipment, reorganized units and prepared positions, while Germany still needed enough firepower to attack them.