1. Nobody owns anything
In a shared mailbox, a message is either unread or read. Neither state tells you whether somebody is dealing with it. The usual workarounds — coloured flags, folder conventions, “I’ve got this” in a group chat — work for two people and fail silently at four.
2. History belongs to individuals
Once a colleague replies from their own address, the thread continues in their inbox. The shared mailbox holds the first message and nothing after it. Six months later, the customer’s history is scattered across four mailboxes, two of which belong to people who have left.
3. Nothing is measurable
A mailbox cannot tell you how long customers wait, how many enquiries you receive, which topics dominate, or who is carrying the load. Every one of those is a management decision made blind.
4. Nothing chases itself
An email that needs following up in three days depends on somebody remembering. The tickets that damage a business are almost never the difficult ones — they are the ones nobody looked at for eleven days.
5. Two people reply differently
Without a shared record, two colleagues can give a customer contradictory answers within an hour, and neither will know. This is the failure customers remember longest, because it looks like incompetence rather than delay.
What to do about it
You do not have to abandon email — customers should keep writing to the address they already know. Route that address into a queue instead of a mailbox, and every one of these five failures is structurally prevented rather than managed by discipline.