Answer: English enjoyed much better ships (better, i.e. fast manoeuvres), much better arms and especially artillery. Better cannons (more than this ..Englishmen had much more and much better cannons) ...it was the key to English victory. Both leaders, Effingham and Drake, were better equiped in all respects.
Explanation: one of the factors was also high and exaggerated self-esteem of Spanish king Filip II. who was too convinced about his victory.