Read the article. Its mostly to do with inertia in large organisations or multiple failed projects to replace old systems

For the people who use this old technology, life can get tedious. For four years, psychiatrist Eric Zabriskie would show up to his job at the US Department of Veterans Affairs (VA) and start the day waiting for a computer to boot up. "I had to get to the clinic early because sometimes it would take 15 minutes just to log into the computer," Zabriskie says. "Once you're in you try to never log out. I'd hold on for dear life. It was excruciatingly slow."

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Most VA medical facilities manage health records using a suite of tools launched by the US government in 1997 called the Computerized Patient Record System (CPRS). But it works on top of an even older system called VistA – not to be confused with the Windows Vista operating system – which first debuted in 1985 and was originally built on the operating system MS-DOS.

The VA is now on its fourth attempt to overhaul this system after a series of fits and starts that dates back almost 25 years. The current plan is to replace it with a health record system used by the US Department of Defense by 2031. "VA remains steadfast in its commitment to implementing a modernised, interoperable Federal [electronic health record] system to improve health care delivery and positively impact patient care," says VA press secretary Pete Kasperowicz. He says the system is already live at six VA sites and will be deployed at 19 out of 170 facilities by 2026.

> start the day waiting for a computer to boot up. "I had to get to the clinic early because sometimes it would take 15 minutes just to log into the computer

Thank god that Windows 11 only needs about 3 minutes to boot up and 2 more to be usable after login in a corporate environment. How the times fly. /s