I have interviewed literally thousands of candidates over the last two decades. Nervousness is part of the dance, even for those candidates that took the time and spent the energy to prepare.
We are our own worst critics. Often, I'll talk to a candidate after an interview and they will be 1) excited about the opportunity, and 2) focus on what they are sure they did wrong while completely overlooking what they did do "right".
That being said, the very best applicants do stand out, they make a lasting impression. Often even those candidates have small awkward moments in an interview, or don't word something quite right the first time around. BUT - there are some major red flags that always make a terrible impression and immediately lead to rejecting the candidate:
1. Inappropriate Conversation: A lot of my first interviews are casual, and this is strategic. I want to get a feel for how the candidate will handle themselves day to day. Curse words, offensive topics, vulgar jokes will all get you disqualified.
2. Superior Attitude: The very essence of interviewing requires you toot your own horn. But a pompous, better than attitude, even if your performance is top notch, is not something many people welcome on to their team.
3. Arrival Time: A well timed arrival is critical to your first impression. A late arrival sends the message you are disrespectful and may be unreliable. An arrival more than 15 minutes early can also be irritating, hiring managers will be scheduled prior to your appointment and not ready for you. You should arrive 10 minutes in advance to ensure you are in the right place, get checked in and settled.
4. Unprofessional Appearance: Today's world does not dictate that you should be in a suit for every interview. In fact, your clothing choices should be dictated by the office environment itself. You should dress several levels above the position you are interviewing for. In a creative environment, you would wear something different than if you are interviewing at a bank. But, no matter where you are interviewing, your attire should be clean, pressed, and fit appropriately.
If a candidate seems unaware of the position details, company focus, doesn't bring a resume, it screams desperation and disinterest. Take some time to do your research, bring your support materials, and have questions for your interviewer.
This is by no means an exhaustive list of interview no-no's. I have heard some incredible answers over the years. To book a consult about your own interview prep plans, visit: https://www.mgassociates.org/book-online.