Usually, people commit only the files they changed. They do not commit their parent folder or even the root folder (which would require to manually exclude those files they don't want to be included in the commit). That's much easier, but as a result, the parent folder or root folder stays on an old revision (see its properties). Unless there is a change in the folder properties, like adding an ignore directive or a merge info. If this happens, the root folder wants to be committed too, and when this is done (maybe without committing anything else), a check for modification in other working copies lists the root folder as modified (properties only) in the repository - and some other operations, like a merge, require it to be updated to head revision first. (a branch does not require this, but it should be done or else the revision tree shows it as branched from a stone-age revision)