audit log doesn't require entry on line add

In P4210, we often have changes to orders as part of customer requirement changes or problems in shipping.  We have turned on the Audit Log on tab 20.  However, when we add a new line to the order because the customer requested a new or different product, the change revision reason isn't always required.

Any insight as to why?

Set Tab - 20 Audit log

1) 1 - Use Audit Log

2) 1 - Reason Code required for Sales Order Changes

Create an order (SO) with several lines

Save the Order

Re-open the order and add a new line (new item or same item (New lot and location)