In addition to data consistency, the export mechanism also ensures data completeness so that, when exporting an object, all possible information involved in the definition of that object and that might be relevant when using it, is also exported.
For instance, when exporting a person, his/her parent organization is also exported, as well as his/her working contexts, so that the resulting export file contains all relevant information associated to the person.
Note:
These dependencies are different from those described above; for example, from a pure syntactic point of view, an export file would still be consistent without a person's business attributes - but it would not be consistent from a global point of view since the information concerning the person wouldn't be complete.