I am not so sure removing the positive wire from the battery while engine running is a great test anymore due to the electronics involved in most cars today. I am not sure about the Kia, but I know on other cars the alternator is just fine, but removing the battery lead will stall the engine. Some items need to be powered by the battery and yes, the alternator may in theory keep it running but not if the manufacturer uses a protection diode to protect electronics from reversals, and surges. That was a great test years ago, but it could lead you astray today on some vehicles.