What is the difference between File Notes and Workflow Notes?
File notes are like a sticky note attached to the file. They are visible to all users that have access to the file, regardless of where it is in a workflow process. An example of a file note is below.
From the File Details page:
Workflow notes are available only to users who have access to the particular workflow step that the notes are on. Once the document moves past that step, those workflow notes are no longer visible. An example of a workflow note is below.