The GB needed to come up with some sort of story on why the end that is just around the corner has not came yet. As already stated, many faithful jw have died. I remember visiting one couple where one was dying. She was told by her husband to just hang on because the paradise is very close. They have both passed away years ago.
1914 is getting farther and farther back and the WTS needs to buy time to keep the jw active in the ministry.