I was looking through the quotes about 1975, and I found something interesting...
This is not the time to be toying with the words of Jesus that "concerning that day and hour nobody knows, neither the angels of the heavens nor the Son, but only the Father." (Matt. 24:36) To the contrary, it is a time when one should be keenly aware that the end of this system of things is rapidly coming to its violent end (Watchtower, August 15, 1968) [emphasis added].
I remember when I started studying with Jehovah's Witnesses around the year 2006... Back then they were also talking about the end all the time. Everyone was saying to me, just a little kid back then, that this world would end within a few years. You would think that they learned something from the 1975 fiasco; but, no, they still continue to "prophesy" that the end of this world is just around the corner. They still do the same thing―with only one exception; now they don't give any concrete dates.