A big part of the whole security clearance process is determining the competency of the individual in recognizing incorrectly classified material. Saying that

A big part of the whole security clearance process is determining the competency of the individual in recognizing incorrectly classified material. Saying that the designated markings were missing is no longer an excuse once you get the clearance. Over two thousand emails were determined to contain classified material, that is over two thousand opportunities to recognize how badly you've screwed up in using a private server for official government business. Twenty of those where classified top-secret, which is really difficult to mistake for uncontrolled information. I'm pretty sure that the issue of competency will be front and center during these interviews.