The Phoebus cartel engineered a shorter-lived lightbulb and gave birth to planned obsolescence. Phoebus expended considerable technical effort into engineering a shorter-lived lightbulb.
How exactly did the cartel pull off this engineering feat? It wasn’t just a matter of making an inferior or sloppy product; anybody could have done that. But to create one that reliably failed after an agreed-upon 1,000 hours took some doing over a number of years. The household lightbulb in 1924 was already technologically sophisticated: The light yield was considerable; the burning time was easily 2,500 hours or more. By striving for something less, the cartel would systematically reverse decades of progress.