Ken Olsen, founder of Digital Equipment Corporation, 1977
Digital Equipment Corporation was acquired by Compaq more than a decade ago, but in the 1970s the company was a major force in the world of computing. Within four years of Olsen's remark, the release of the IBM PC had enshrined this prediction in the high-tech hall of shame.
Ken thought of computers as tools of industry. He had this idea that computers were big and specialized tools, and he did not diverge from that idea.
But innovations need to keep being innovated on. Or else we get stuck. At some point, someone asked something like, 'what if this were smaller?'
Source:
http://www.pcworld.com/article/155984/worst_tech_predictions.html