When you get a new notification for a new ticket. More than one agents can answer the same time with no notice of each other.
petervanbeugen commented on Jan 22
I agree that the possibility to lock tickets (system wide on/off/auto setting?) is essential. In higher ticket /agent volume environments this becomes a nightmare. I’m a heavy OTRS user and have a (Znuny developed) package to be able to auto-lock a ticket as soon as it is opened by an agent. This would be nice in Zammad as well… A temporary workaround in Zammad could be to add a field in the Overwiews where you can see if a ticket is in use by an agent.
I like the idea and cane imagine use cases to work with more than one agent on a ticket, but then it should be possible to invite another agent to the ticket.