In the lead up to WWI, as warfare shifted from fighting at close quarters to heavier artillery fired from greater distance, it become advantageous to conceal soldiers for as long as possible.
在第一次世界大战前夕，随着战争从近距离战斗发展为从更远的距离进行重炮射击，尽可能长时间地隐蔽士兵就能占据优势。