They want someone who does not study for an interview but is more concerned about the NEXT guy getting the job instead of you.
OK, let me blow this theory out of the water. When I was leaving active duty AF, a squadronmate and I were trying to get hired at the same Guard unit. I knew that there was room for both of us; they were moving from ORD to Scott AFB.
In the interview, I was asked if they only had one to take, who would it be - him or me. I said to take him. I found out later that he had been asked the same question, but told them to take him. He didn't get hired at the Guard unit; I did.
Where's that backstabbing squadronmate now? At Southwest. I never applied there; my goal in life is to doze for dollars as a relief FO on the 777 or 747. United was a much better fit for me. Of course I've been furloughed for almost five years while he's been working at Southwest.
As for the squadronmate, I doubt that he changed for his Southwest interview.