The warehouse system example has been stuck with me for a few years. I haven’t successfully applied it (it’s hard to change how people think). In any case, this example has so many points of interest it’s eye opening.
First, the idea of the “source of truth” - we get so stuck in defining the software as the source of truth, when in reality the source of truth is always “the real world”. As a corollary, in some cases, the “proxy” source of truth is actually another piece of software, when all we can do is interact with a third party system. In many cases we cannot ensure good data, because the system cannot guarantee it.
Second, the idea of an exception report. It can be used in so many realms for improving quality. The software of record may not be able to generate or ensure valid inputs due to the many uncontrolled aspects of it, but it can help users find the irregular situations and help “correct” that data (in the case of an event sourced system, with a new event ensuring the correction is an entry).
“It’s a different perspective, that also changes how a domain expert looks at a domain”