* You have a huge Excel document that's basically a DB. (What Access kinda was)
* You want users to interact with said data document, i.e add record, find/query record(s), edit records
* You add a "form" for users to do just that. You can also add a "login" form to give some users more permissions.
It's basically if you could turn a SQlite file into a low-coded desktop app.JET Blue aka ESE is currently used by products like Active Directory and Exchange.