Hello
When setting up preventative maintenance tasks it makes sense to use Categories and maybe sub-categories and Items along with them. However, you probably don't want your user base to see some of those categories with their associated sub-categories or items.
For example, you might have a Category = "Backups and sub-categories "Initialise Backups" and "Check backups".
You might not want the average user submitting a ticket with backup as a category so it makes sense to add a flag the admin can set when creating the Categories, Subcategories and Items that says "Don't display to general user"