That&#x27;s because the opening is 17 moves deep when the error is made. You&#x27;re entering mid game at that point. Ruy Lopez, Queen&#x27;s Gambit, Sicilian, Dutch, and King&#x27;s Indian defenses, Stonewall, others, are generally preferred, because of their strengths. But if you&#x27;re not familiar with them 17 moves deep, and several of their variations, you&#x27;re screwed. There&#x27;s a reason why you have &quot;Encyclopaedia of Chess Openings&quot;- it&#x27;s the disproportionate strength of chess.