When a developer checks out a file, the checked-out version is locked in the Repository, and a local copy is made in the developer's PWE. When a developer is satisfied with changes he/she has made to a checked-out file (compilable!), he/she checks it back in. This means that the new (checked-in) version replaces the older (checked-out) version in the Repository. However, the SSWE still has the older version of the file, and the objects in the SOWE are also based on this version.
Clearly, the working environments are no longer consistent with each other, and they need to be updated so that all PWEs (i.e., their owners) can access the most current state of the project.
Updates should be done on a regular (daily) basis, especially if you have a large development team. The shared working environments (SSWE and SOWE) should only be updated by the Working Environments Administrator. Although it is relatively natural for individual developers to update their PWEs when they start work, this can also be done by the Working Environments Administrator.
You update your working environments in the following order: