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

What you do during a job interview can be just as important as your qualifications and experience. Candidates sometimes make a poor impression through avoidable behaviour, even when they have the skills required for the role.

This guide focuses on what not to do during a job interview and how to handle common situations more professionally. For complete preparation before, during and after the interview, read our job interview preparation guide.

1. Do Not Arrive Late Without a Good Reason:

Arriving late can create a poor first impression and may disrupt the interviewer’s schedule. Plan your journey in advance and allow extra time for delays.

If an unavoidable delay happens:

Contact the employer as soon as possible, explain briefly and professionally, and ask what they would prefer you to do.

2. Do Not Treat the Interview Casually:

An interview is a professional conversation. Being friendly is helpful, but becoming overly informal too quickly can make the wrong impression.

Match the professional environment:

Pay attention to how the interviewer communicates and keep your language respectful and appropriate to the workplace.

3. Do Not Interrupt the Interviewer:

Interrupting repeatedly can make it appear that you are not listening. Allow the interviewer to finish the question before responding.

Listen for the full question:

Some questions contain several parts. Take a moment to make sure you understand what the interviewer is asking before answering.

4. Do Not Give One-Word Answers:

Very short answers can make it difficult for an interviewer to understand your experience. Give enough context and evidence to explain your point.

Use examples where they add value:

When discussing a skill or achievement, support your answer with a relevant example. Competency questions often work well with a structured approach such as STAR.

For detailed examples, see our guide to competency-based interview questions and answers.

5. Do Not Give an Unrelated Answer:

Prepared answers are useful, but they should not replace listening. Answer the question you were asked rather than forcing a memorised response into the conversation.

Ask for clarification when necessary:

If you are genuinely unsure what a question means, asking for clarification is better than guessing.

6. Do Not Speak Negatively About Previous Employers:

You may have left a previous role because of genuine difficulties, but avoid turning the interview into a complaint about a former employer or manager.

Keep the focus on the future:

Explain what you are looking for in your next role and how the new opportunity fits your goals.

7. Do Not Exaggerate Your Skills or Experience:

Claiming knowledge or experience you do not have can create problems when interviewers ask follow-up questions or test your understanding.

Be honest about your level:

You can discuss your willingness to learn without pretending to be an expert. Employers often value honesty and self-awareness.

8. Do Not Check Your Phone During the Interview:

Unless you are dealing with an agreed emergency, keep your phone silent and out of sight. Checking notifications can appear disrespectful and distracting.

9. Do Not Forget About Body Language:

Body language is only one part of communication, but visible signs of distraction or disengagement can affect the overall impression you make.

Keep it natural:

Do not try to perform artificial body language. Instead, focus on listening, sitting comfortably and engaging naturally with the conversation.

10. Do Not Ask Questions That Have Already Been Answered:

Questions are important, but asking something the interviewer has already explained can suggest that you were not paying attention.

Prepare questions but adapt them:

Bring a short list of questions and cross out any that are answered naturally during the interview.

11. Do Not Assume the Job Is Already Yours:

Confidence is useful, but acting as though you have already been hired can come across as overconfident.

Show interest without pressure:

Explain why you are interested in the opportunity and demonstrate your value without making assumptions about the outcome.

12. Do Not Leave Without Understanding the Next Steps:

Before the interview ends, it is reasonable to ask about the next stage and when candidates can expect to hear back.

How to Behave Professionally in a Job Interview?

• Listen carefully before answering.
• Speak clearly and honestly.
• Give relevant examples.
• Respect the interviewer’s time.
• Stay professional even when discussing difficult experiences.
• Ask thoughtful questions.

For five of the most common preparation mistakes, see 5 common job interview mistakes to avoid.

What to Do Instead of These Common Interview Behaviours?

Prepare, but stay flexible:

Prepare examples and key talking points without memorizing a script. This helps you respond naturally to follow-up questions.

Stay focused on the role:

Keep bringing your answers back to the requirements of the vacancy and the skills the employer is trying to assess.

Use the interview as a two-way conversation:

An interview helps both sides decide whether the opportunity is a good fit. Listen, answer clearly and use your questions to understand the role better.

For the full process, including preparation, common questions, remote interviews and follow-up, visit our complete job interview preparation guide.

Frequently Asked Questions:

Is it bad to be nervous in a job interview?

No. Interviewers understand that candidates can be nervous. Preparation and taking a moment before answering can help you manage nerves.

Should I tell an interviewer about a bad previous job experience?

You can answer honestly when relevant, but keep your explanation factual and professional. Avoid personal attacks or lengthy complaints.

Can I ask the interviewer to repeat a question?

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

Final Thoughts:

Good interview behaviour does not mean acting like a different person. It means showing respect, listening carefully, answering honestly and keeping the conversation professional. Avoiding these common behaviours can help your skills and experience receive the attention they deserve.