The text discusses the limitations of PostgreSQL in financial services, emphasizing its challenges with horizontal scaling, distributed architecture, and managing downtime. PostgreSQL, despite its stability and ACID compliance, struggles with scaling horizontally, which is crucial for processing numerous transactions per second, and often requires manual sharding that is costly and risky. The distributed architecture of PostgreSQL also presents issues, as it relies on a single write node, creating bottlenecks in distributed transactions. Furthermore, PostgreSQL is not well-suited to handle unplanned downtime caused by unforeseen events, and planned downtime for updates can be costly. The article highlights why Stash migrated from PostgreSQL to CockroachDB, a fully distributed SQL database that offers better scalability, resilience, and lower latency. CockroachDB's ability to scale out both reads and writes across regions made it an attractive option for Stash, ensuring high availability and multi-region, multi-cloud capabilities.