However, unless factors such as those listed above are allowed to work, a society's birth rates may not drop to a low level in due time, which means that the society cannot proceed to stage Three and is locked in what is called a demographic trap.
然而，除非允许上述因素发挥作用，否则一个社会的出生率不可能在适当的时候下降到低水平，这意味着社会不能进入第三阶段，并且陷入所谓的人口陷阱。