7 mistakes that can derail a promising job interview

Applying for your next big career opportunity requires a lot of work. You need to reach out to your network, arrange informational meetings, talk to recruiters, submit résumés, prepare talking points, and ace the preliminary interview.

Finally, you land the final interview that will seal your fate. Success at this stage is not so much about whether you have strong credentials—you wouldn’t have made it this far if you didn’t. It’s a matter of making sure you don’t veer off course during the meeting.

Beware of the following seven things that can derail your interview at this all-too-critical stage of the game:

1. NOT LOOKING THE PART

Your appearance makes a huge difference—that is the conclusion of a recent study by JDP, a consumer reporting agency specializing in background screening. The majority of respondents said they worry that some aspect of their dress will cost them the job.

Here’s my advice: Research the way people dress in that company, and dress a cut above that. A job interview is a formal event, so dress as you would if you were making a client presentation in that firm, or having a meeting with senior management. In many instances that means wearing a suit or jacket, and making sure your top and bottom coordinate.

2. GOING OFF MESSAGE

Straying from your message in a job interview can be dangerous if it makes you sound unfocused. Make sure to bring every answer back to why you are a highly desirable candidate.

If asked about your former boss, for example, show how he mentored you in ways that make you ready for this new assignment. If you’re asked about a time when you failed at something, tie that back to lessons learned that will help you in your new role. If you are asked about volunteer work you’ve done, show how it reflects the values you bring to the company. Reinforcing the same message over and over again may feel repetitive to you, but it will make you sound focused to the interviewer.

3. GETTING INTO YOUR PERSONAL LIFE

You’ll come to the interview prepped with key messages, but if the discussion moves into personal topics, gracefully shift back to your core arguments.

Some interviewers will quiz you about your personal life. According to the JDP study, more than half of job candidates (59%) are asked about their personal life, and 37% of women are queried about their plans for children, despite the fact that this is illegal. Interview questions about parental or marital status—as well as race, religion, sexual orientation, age, or disability—are not permissible under Federal Equal Employment Opportunity laws.

That doesn’t always stop interviewers from asking. When I was 37, I interviewed for a speech writing job. The CEO for whom I’d be writing said out of the blue, “Well, at your age thankfully you won’t be having any more children.” I remained silent, passed up the job, and had a child at age 44.

Besides being inappropriate, these personal questions can derail you from your professional pitch. You can get caught up in “well, I’m not sure,” or “my partner and I are just starting out, we don’t know if we want children,” and before you know it, you’re sharing more than you like. If you feel any topic raised is out of line, return to the points that will help you get the job.

4. BECOMING RATTLED BY A QUESTION

Questions can fly at you from all directions, and it’s important that you not get rattled. Take time to answer each question, and prepare as fully as you can.

For example, suppose you’re asked about a recent project you led, and you freeze, unable to think of an answer. Don’t start babbling, which is what we often do when we’re nervous. Instead, pause, think it through, and provide a thoughtful answer. You’ll look more confident because you’re not afraid to take a moment to collect yourself.

More broadly, prepare answers to as many questions as possible. By spending time in advance thinking through the tough questions, you’ll ace them when they come to you.

5. GETTING TOO CHUMMY

If you’re lucky enough to bond with the interviewer, be wary of becoming too familiar with that person.

Let’s say she compliments you on your shoes or your shirt, and suddenly you feel the two of you are friends. This might lead to your tone becoming less grounded and your words becoming less polished and more akin to the language you use in everyday chats with friends.

You might even disclose things that are better left unsaid, such as, “You know, this interview process has been awfully long, and I’m glad we’re at the end of it.” While it’s good to develop a friendly rapport, stay on a professional footing.

6. LOSING YOUR CONFIDENCE

In the interview, there may be moments that surprise you or unnerve you, but that’s when it’s most important to remain confident.

The interviewer may disclose, for example, that there are nine other candidates being interviewed, when you thought you had been short-listed. Avoid dropping your eyes, showing disappointment in your face, or slouching in a body position that shows you’re disheartened.

Instead, sit tall, make direct eye contact, keep your arms open, and keep a receptive expression on your face.

7. NOT CLOSING

As the interview winds down, reaffirm your interest in the position and ask about next steps. Many candidates walk away from a job interview feeling confused about how they did, and what the future holds for them.

In affirming your interest in the position, you might say, “I was excited about this opportunity when I came in today, and I am even more excited now.”

Asking what the next steps are further reinforces your commitment. It also can elicit from the interviewer some sense of where you stand. If your future boss says, “I have enjoyed our discussion, and we’ll get back to you within a week,” that’s cause for believing it’s full steam ahead for you.