1975 was a bad year for Jehovah's Witnesses. They expected Armageddon to come then. Many witnesses postponed marriage, having children, or surgery because they thought the end was so close. Others quit their jobs or sold their homes. Afterwords when nothing happened, the leadership failed to apologise and indicated that their members were to blame coming to the wrong conclusion about 1975. This recording of a talk from around 1967 by Charles Sunutko gives an indication of how 1975 was hyped by their leaders.
STAY ALIVE 'TIL 75! (Talk by Charles Sunutko)
Also consider what was said in the May 1974, Kingdom Ministry on page 3, "Reports are heard of brothers selling their homes and property and planning to finish out the rest of their days in this old system in the pioneer service. Certainly this is a fine way to spend the short time remaining before the wicked world's end."
Please also see this page for many more direct quotes about 1975.