It was just hidden previously and swamped by a more crude difficulty and, when the cruder difficulty is explained away, people focus their attention on the new difficulty.

先前它只是隐匿起来了，被更加粗糙的困难所淹没，并且在这些粗糙的问题被解决之后，人们才将他们的目光聚焦在这个新问题上。