IMO, a typical use case is as follows.
Customers will send an email to a common email address say, support@mycompany.com
all emails drop into OSTIcket for any other CRM for that matter.
This mailbox is managed by a group of support reps.
As an agent, when I see a new email (its unassigned), I reply to it.
When I reply to any unassigned ticket, its like I take ownership of that ticket. So the CRM will make it "my ticket".
This is the workflow for all support reps.
Each of the support reps can see un-assigned tickets and their own tickets. We cannot see tickets owned by other support reps unless its assigned manually.
Our manager can see all tickets & their owners.
I work for a help desk company & we have worked with almost 20 CRM applications: Zendesk, Zoho, Freshdesk, Desk, Salesforce, Service Now, to name a few. The workflow is the same in all these tools.
Just sharing my 2 cents if it helps make OSTicket better