Startups opting for CockroachDB over PostgreSQL can benefit from its features tailored for distributed systems, such as SQL compliance, high availability, and data locality, which are crucial for scalable applications. CockroachDB offers PostgreSQL compatibility, facilitating an easier transition for those familiar with PostgreSQL, while providing advantages like ACID compliance and serializable isolation to ensure data correctness despite high transaction volumes. The database's ability to maintain high availability is emphasized through recommended configurations, such as using a minimum of three nodes across availability zones, and operational best practices like regular backups and proper node decommissioning. Additionally, leveraging SQL best practices for distributed systems, such as smart schema design, strategic indexing, and adopting Universally Unique Identifiers (UUIDs), can significantly enhance performance and avoid common pitfalls as startups scale.