How the Liability Account is updated automatically when Employee becomes Supplier

Hi All,

I need to understand as -  How the Liability Account on Supplier Page is updated automatically when Employee becomes Supplier. Please refer below steps we followed to create an employee as a supplier in AP.

1. New Employee Created in HRMS responsibility.
2. This new employee submits the Expense Report in iExpense Responsibility.
3. After manager approval of this expense report, it creates the AP Invoice & at the same time this employee becomes the Supplier in payables.
4. Now when this employee becomes the supplier; the liability account gets updated automatically on Supplier Page

     (Navigation - Search Employee Supplier: Accounting -> Liability tab -> Liability Account)