One classic way this goes wrong is when we forget the “human intervention” part.
You end up with these Kafkaesque nightmares where somebody is stuck in an infinite product return loop or their insurance claim is denied or the state thinks they’re dead or they get a zillion parking tickets because their custom license plate spells “NULL” (https://arstechnica.com/cars/2019/08/wiseguy-changes-license-plate-to-null-gets-12k-in-parking-tickets/)…and a human is stuck in process hell because •the software just does that• and software is hard to change.