With the introduction of shared storage into a Final Cut Pro X team, workflows tend to open up and become more sophisticated.
Smaller workgroups usually begin by keeping FCPX libraries and their corresponding media in the localized, self-contained bundles FCPX uses by default. This is a logical way to work for very small teams, especially when there’s no shared storage. But, while this works acceptably for smaller, condensed environments, this workflow shows itself to be less efficient with the addition of network storage and increased users/collaboration. As your team grows and more users need more assets, it can be better to have media stored separately from libraries.