What Not to Do in a Job Interview: 12 Mistakes to Avoid

A job interview is a professional conversation, but small behaviour mistakes can distract from your skills and experience. The aim is not to behave like a perfectly rehearsed candidate. It is to communicate clearly, listen carefully and give the interviewer enough information to understand your suitability for the role.

This guide focuses on mistakes that can happen during the interview itself. For complete guidance on preparation, interview questions and what to do afterwards, read our Job Interview Preparation: Complete Guide.

1. Arriving Late Without Contacting the Employer

Arriving late can disrupt the interview and create a poor first impression. Plan your journey or video-call setup in advance and allow reasonable time for unexpected problems.

If an unavoidable delay happens, contact the employer as soon as you can, explain briefly and follow their instructions.

2. Treating the Interview Too Casually

You can be friendly without becoming overly casual. Match your language, behaviour and clothing to the professional setting and the type of organisation.

The goal is not to appear overly formal. It is to show that you understand the interview is an important professional conversation.

3. Interrupting or Failing to Listen

Allow the interviewer to finish the question before responding. Some questions contain several parts, and answering too quickly can mean you miss what is actually being asked.

Take a moment to think if necessary. Asking for clarification is better than answering a question you have misunderstood.

4. Giving Answers That Are Too Short or Too Long

One-word answers make it difficult for an interviewer to understand your experience, while long answers can lose focus and use valuable interview time.

Answer the question directly, provide enough context and use an example when it helps demonstrate your skills or contribution.

5. Forcing Memorised Answers Into the Conversation

Preparation is useful, but a memorised answer may not fit the exact question being asked. Listen first and adapt your prepared examples to the conversation.

For competency questions, prepare real examples rather than trying to memorise a complete speech.

6. Speaking Negatively About Previous Employers

You may have had genuine problems in a previous job. However, personal attacks or lengthy complaints can distract from your reasons for moving on.

Keep your explanation factual and professional, then focus on what you want from your next role.

7. Exaggerating Skills or Experience

Do not claim expertise that you cannot explain or support. Follow-up questions may quickly reveal exaggeration.

It is usually better to explain your genuine level of experience and show that you are willing to develop a skill where appropriate.

8. Using Your Phone Inappropriately

Keep your phone silent and out of sight unless there is an agreed reason you may need to respond to an urgent situation. Checking notifications during an interview can interrupt the conversation and suggest that your attention is elsewhere.

9. Trying Too Hard to Control Your Body Language

There is no perfect interview posture or facial expression. Trying to copy artificial body-language rules can make you more self-conscious.

Instead, focus on sitting comfortably, listening, maintaining natural engagement and communicating clearly.

10. Asking Questions That Have Already Been Answered

Prepare questions in advance, but listen carefully throughout the interview. If a question has already been answered, choose another one.

Useful questions often help you understand the priorities, team, expectations or next stages of the process.

11. Assuming the Job Is Already Yours

Confidence is useful, but assuming that you have already been selected can appear overconfident. Explain what you can offer without treating the decision as complete.

A professional interview should leave room for the employer to assess you and for you to assess whether the role is suitable.

12. Leaving Without Understanding the Next Steps

Before the interview ends, it is reasonable to ask what happens next and when candidates can expect an update.

This gives you a clearer understanding of the process and helps you avoid unnecessary follow-up before the employer’s stated timeframe.

How to Handle Difficult Moments During an Interview

If You Do Not Know the Answer

Do not invent information. Take a moment, ask for clarification if needed and answer honestly based on what you know.

If You Become Nervous

Nerves are common. Slow down, take a breath and focus on the question in front of you rather than trying to predict the entire interview.

If You Make a Small Mistake

A minor mistake does not automatically ruin an interview. Correct yourself if necessary and continue with the conversation.

A Simple Interview Behaviour Checklist

• Listen to the full question.
• Answer the question that was actually asked.
• Keep answers focused and relevant.
• Use genuine examples.
• Stay professional when discussing difficult experiences.
• Be honest about your skills and experience.
• Keep distractions away.
• Ask useful questions when given the opportunity.
• Understand the next steps before leaving.

Common Myths About Interview Behaviour

You do not need to dominate the conversation, maintain constant eye contact or use a perfect rehearsed answer to make a good impression. These rules can make candidates focus more on performance than communication.

A stronger approach is to listen, answer clearly and give the interviewer useful evidence of how your experience relates to the role.

Frequently Asked Questions

Is it bad to be nervous in a job interview?

No. Many candidates are nervous. Preparation and taking a moment before answering can help you manage your response.

Can I ask an interviewer to repeat a question?

Yes. Asking for a question to be repeated or clarified is better than answering something you did not understand.

Should I discuss a bad previous job experience?

You can answer honestly when relevant, but keep the explanation factual and professional. Avoid personal attacks and focus on what you want to do next.

Should I ask about salary in the interview?

Salary may be discussed at different stages depending on the employer and role. If the topic arises, answer professionally. You can also ask about compensation when it is appropriate to the stage of the process rather than treating the subject as automatically off-limits.

Final Thoughts

Professional interview behaviour is not about pretending to be someone else. It is about making it easier for the interviewer to understand your experience and suitability.

Listen carefully, answer honestly, avoid unnecessary distractions and keep your examples relevant to the role. For broader support, read our Job Interview Preparation: Complete Guide, 5 Job Interview Preparation Mistakes to Avoid and Why Good Candidates Fail Job Interviews and How to Improve.