In a distributed database system, strict serializability provides the strongest guarantee for correct execution of transactions. It ensures that transactions respect real-time order and integrity, surpassing traditional isolation levels like serializability and linearizability. This correctness model eliminates anomalies such as stale reads and causal reverse, making distributed databases more intuitive and reliable. A system that supports strict serializability prevents these issues by providing a serializable execution of transactions while ensuring real-time causality, thereby guaranteeing the consistency of data across all replicas in a distributed database.