This was first said in 1918 and adjusted to "will never die" in 1920. Of course, the WTS taught that the anointed had to die to go to heaven; but there was no great crowd teaching then, so they were talking about all non-anointed people on earth. The WTS members were known as Bible Students then and had been expecting the end in 1914 and it was adjusted. One date that was stressed at that time was 1925. So I think they idea was that people living in 1918 would be alive to see the end in 1925, which of course did not happen. So not lying, but true believers who were disappointed again. About 3/4 of the Bible Students stopped coming and partaking at the Memorial after 1925.
http://www.jwfacts.com/watchtower/1925.php
Not until 1966 did the WTS again put forth a date with certainty, 1975. Came and went and the WTS lost 2% of their membership each year for 2 years after that.
But they did say that many jws would live through Armageddon, never dying, leaving loopholes. The jws in my mother's generation are almost all gone....those that hoped they were among those who would never die. I wondered what they were thinking as they breathed their last. That they would wake up in paradise?
I always wondered why escaping death would be such a "privilege"? Down to today, every human on earth has died, even Jesus. No one has escaped it yet. Noah his family lived through the flood but died later. Lazarus was resurrected but died again.
Was Jesus saying at John 11:26 (speaking to 1st century followers) that they would never die at all? Or was he talking about another kind of death? Or was he referring back to the resurrection and saying those that were resurrected at a future time would never die after that?
(remember I am just reporting WTS teachings not supporting them as my own)