If a global update has to be done, then the global update will be performed on all retrieved records. It would be nice if all records that have to be updated should be checked by a checkbox.
Retrieve the records on which a global update has to be done. Default all records are checked with a checkbox. It is also possible to disable all checked checkboxes of all retrieved records with a single checkbox standing in the header of the grid. The same kind of concept can be found in the screen where deployment archives can be made (after pushing the add button).
The current situation is that it's only possible to retrieve all records or the wanted records by using wildcards in a retrieve profile. Using checkboxes as an additional option is a convenience so you don't have to think very hard about very long retrieve profiles with wildcards. Or save the time to perform manual actions.