I only have one group set up in my Support account. Why are my tickets all being automatically assigned to the group?
If you only have one group set up in your Support account, all tickets will automatically be assigned to the group. To get around this, you can create a dummy group to ensure you have more than one group in your Support account. See About the system inborn ticket rules for more information.
I have multiple groups set up in my Support account. I don't have any business rules which would automate group assignment. However, some of the tickets are still being automatically assigned to a group. What is causes this behavior?
In this case, the auto-assignment most probably occurs due to the ability to map a group to an organization. This functionality can be enabled or disabled on the organization profile page.
If there is a group selected in the Group field then all new tickets submitted by users who are part of the organization will be automatically assigned to this specific group. To avoid auto-assignment simply set the value of this field to null.
See Creating, managing, and using organizations for information on mapping a group to an organization.