Literally any electronic medical record system ever built. HUNDREDS of different systems on the market. Some with maybe a handful of doctor's offices using a

Literally any electronic medical record system ever built. HUNDREDS of different systems on the market. Some with maybe a handful of doctor's offices using a particular system. Worst UIs you could ever imagine. Limited interoperability. In even well-established systems with large numbers of installs you'll see multiple bugs in production code that don't get fixed. Switching costs are essentially infinity so doctors get locked into a system no matter how bad it is.