"But it seemed to go so well! We talked about everything… campus life… the weather… the football season. I just don't understand why I got a rejection letter…"
Beware the interview that gets too chummy. It may be that the interviewer has already rejected you and out of politeness passes the remaining time talking about everything but you.
First impressions count. Often for far more than is logical.
The truth about interviewing is that most initial interviews last only about five minutes. Oh, sure, the actual interview always takes longer than that. Twenty minutes. Thirty minutes. Sometimes even an hour. But the interview is usually over in five minutes or less. If you have not convinced the interviewer by the five-minute point that you are the right person for the job (or at least a contender who should be taken to the next level), it can be next to impossible to recover. Recoveries do happen. But they are very rare.
In that first five minutes of the interview, I will have noted many critical aspects. Your appearance. Your grooming. Your handshake. Your personal presence. Your eye contact. Your articulation. And, most important, your personality. Notice that I did not mention anything about your coursework, your GPA, or your work experience. That is what got you to the interview in the first place. But it is the "soft factors" that will take you to the next level.
Having taken the right courses, having good grades (critical!), and having related work experience are all important selection criteria. But they do not matter one iota if you are not a strong interpersonal fit for our company.
The truth is that most interviewers rate individuals highly who are able to present themselves well in a face-to-face interview. They are seeking to recommend those who will be a good reflection upon themselves and their selectivity. So most interviewers naturally gravitate to specific "critical success factors" that have worked for them consistently.