Beyond CAP Theorem

The CAP theorem has a blind spot. It describes what happens during a partition and says nothing at all about the rest of the time.

That is a problem, because the rest of the time is almost all of the time. Partitions are rare events. Your system spends its life in the healthy state, and CAP is silent about it.

What CAP Leaves Out

Go back to strong consistency. To guarantee that every read sees the latest write, a system has to spread each write to its replicas before confirming it. Those replicas sit on other machines, sometimes in other regions, and reaching them takes real time.