They pointed out that the scriptures do not say that every individual has to be preached to .
W10 9/15, page 10, Para 12:
We recognize that the end could come at any time; Jehovah’s timing is not contingent on our giving a personal witness to every individual on the planet. (Matt. 10:23) Moreover, we receive good direction on how to carry out our preaching work effectively. In faith, we participate in this work to the best of our ability, using whatever resources are at our disposal.Will we always preach in the most productive territory? Really, how could we know in advance? (Read Ecclesiastes 11:5, 6.) Our job is to preach, trusting that Jehovah will give us his blessing.
Matt 10:23: When they persecute you in one city, flee to another;+ for truly I say to you, you will by no means complete the circuit of the cities of Israel until the Son of man arrives.