If you are responsible for securing databases, SQL Servers and others, I would strongly urge you to read the following post by Andreas Wolter, former data security PM for Microsoft. In this post, he talks about implementing audit trail effectively.
Recommendation for Security Auditing for databases – with example for Microsoft SQL Server
In the post, Andreas gives the impact, including to Microsoft, for not-enough auditing. But he also covers background noise and alert fatigue, which reduces the effectiveness of proper auditing. Finally, and of great value, he lays out exactly what to do in Microsoft SQL Server and also gives links to other platforms.