AA seems, as others have said, to use the final face to face as the last check to validate the screening process that has brought a candidate they really want to hire to the final gate. The recommendation letters are a big part of the initial process. And, almost everyone who gets the face to face is most likely military, a group AA literally bends over backwards to procure to mix into the flows. These military pilots are pretty much a known entity, homogenous, and proven to have passed the test. So, they do get hired at a high percentage because of the earlier gates they cleared.