When configuring e-mail accounts in LiveAgent you might have noticed the Alias box.
What is that for?
Well, sometimes some people or company might have several e-mail addresses pointed to a particular e-mail folder (account), so that those e-mail addresses use a common inbox (this is configured in their mail server).
E.g.:
product1@mycompany.com
product2@mycompany.com
might be pointed to sales@mycompany.com that is the common inbox (the real mail account) of those e-mail addresses.
The company is using LiveAgent to provide support to their customers and they are fetching the emails from sales@mycompany.com, while they defined both product1@mycompany.com and product2@mycompany.com as alias when configuring the e-mail account inside LiveAgent.
Let's imagine that customer John sends an email to sales@mycompany.com while into CC (carbon copy) he adds product1@mycompany.com.
At this point in LiveAgent there will be a ticket created and when the agent hits reply the reply will go ONLY to customer John thanks to the defined alias.
If the e-mail address of product1@mycompany.com was not defined as an alias, product1@... would be added as ticket recipient, and the reply would go also to that address and suddenly the reply would be a 'new email' in the inbox of sales@mycompany.com and LiveAgent would fetch that reply as a ticket. This way we could get into a loop.