Assigned Customers are customers who have had jobs done in the past or already scheduled an upcoming job. These are typically listed under the specific representative that originally created the customer profile/estimate.
These, of course, can be reassigned to other users.
To get to a specific employees "Assigned Customers" you'll need to go to the top of your screen and click "Manage > Human Resources"
This will prompt a list of all the employees in your system.
Once there, just select the employee that you wish to view "Assigned Customers" for, this will open up their information, or "Identity" page.
From the employee information page you should see tabs at the top displaying the various areas of information you can look at, specific to that employee.
If you look at the lower row of tabs you will see "Assigned Customers"
(as displayed in the screenshot above)
Once there you will see a list of all the "Assigned Customers" specific to that employee.