Remember pagers? They were huge in the 80s — these little devices that could receive short messages. Sir Mix-A-Lot even had a song about them! But then cell phones came along, and pagers more or less became obsolete.Except there's one group of people who still carry pagers: medical doctors. At a surprisingly large number of hospitals, the pager remains the backbone of communication. Need to ask a doctor a question? Page them. Need to summon a doctor to an emergency? Page them. And then... wait for them to call you back.Almost everyone agrees that pagers are a clunky and error-prone way for doctors to communicate. So why do so many hospitals still rely on them?On today's show: A story about two doctors who hatched a plan to finally rid their hospital of pagers. And the surprising lessons they learned about why some obsolete technologies can be so hard to replace.This episode was hosted by Jeff Guo and Nick Fountain. It was produced by Sam Yellowhorse Kesler. It was edited by Keith Romer and fact-checked by Sierra Juarez. It was engineered by Robert Rodriguez with help from Maggie Luthar. Alex Goldmark is Planet Money's executive producer.Help support Planet Money and get bonus episodes by subscribing to Planet Money+ in Apple Podcasts or at plus.npr.org/planetmoney.