Problem/Motivation
This is a follow #2562845: Validate file path on Credential form up to correct the source path field labels on the Credential Form. In #74 phenaproxima suggested changing 'Private file' to 'Private files. Is that what should be done?
Noting that on admin/config/media/file-system the singular, 'file' is used as in 'Public file' and 'Private file'. Yes, the context is different but maybe use that form as a guide?
Drupal 7 version before:

Proposed resolution
Drupal 7 version with new title.

No change to the Drupal6 version.

Remaining tasks
Decide on the text
Write a patch
Review
Commit
User interface changes
Yes, the label for the 3 source path fields on the Credential form.
Comments
Comment #2
quietone commentedChanged the title field from 'Private file' to 'Private files' for the d7 version of the form. Attached is a before image and an after image of both the d6 and d7 version of the credential form. There is no change to the Drupal 6 version, it is just included for comparison.
Comment #4
quietone commentedSilly me didn't update the test as well.
Comment #5
heddnFairly simple text change that aligns with the actual name of things. LGTM.
Comment #6
alexpottCommitted c023840 and pushed to 8.6.x. Thanks!
This is really good because then there is one less translation. We have
'title' => t('Private files directory'),in system_requirements().