Projects can contain assets that have links to other assets, which themselves can be checked out to other projects. When dependencies like these occur between multiple projects, the content administration system requires all projects to be deployed together, in order to preserve the consistency of data on the target site.
For example:
Project A contains an image file. This project is not yet deployed.
Project B contains some text that includes a link to the image in project A.
Deployment of project B automatically triggers deployment of project A.
