Terry,
Some have speculated that the book of John really ends twice.
Acts 20:30 ends the real book of John: "To be sure, Jesus performed many other signs also before the disciples, which are not written down in this scroll. But these have been written down that you may believe that Jesus is the Christ the Son of God, and that, because of believing, you may have life by means of his name.
The added chapter 21 ends as follows: "There are in fact many other things also which Jesus did, which if ever they were written in full detail, I suppose the world itself could not contain the scrolls written."
Some scholars believe the 21st chapter of John was cut and pasted from the original last chapter of Mark which ends very abruptly. But if you read chapter 16 of Mark and then go strait to John chapter 21 it seems like it is a continuation.
The motive was a power struggle between those following John and those following Peter. The Peter cabal subtly linked John with the betrayer in vs. 20 and most of the 21st chap of John focuses on the honorable death of Peter as a martyr whereas John would at worst die a natural death or even be present to be raptured up to heaven.
There will not be a discussion of this concept in the Watchtower. EVER.