Why do some unshared storyboards still display shared with users and roles?

When you unshare a previously shared Storyboard, you may notice that the 'Shared With' column still shows the roles that it was previously shared with.

Our product team has designed Storyboards to remember the roles with which they had been shared so that when you're ready to push your copy/updated Storyboard back out, instead of needing to remember what roles had originally been selected and assign their levels of access again, you'd be able to just click 'Share' and those roles from before will gain the access they had previously. You have the option to change, add or modify the roles/permissions before sharing again.