Landing an interview means your CV did its job. But now the pressure is on you. According to research by LinkedIn, 73% of hiring managers have a firm opinion of a candidate within the first 5 minutes of an interview. That leaves very little margin for error.

The mistakes below aren't about intelligence or ability — they're about preparation and awareness. Eliminate them, and you'll consistently perform above your competition.

Mistake 1: Not Researching the Company

Walking into an interview without knowing what the company does, who their customers are, or what their recent news is, signals a lack of genuine interest. Hiring managers will almost always ask "What do you know about us?" — and a vague or wrong answer is a red flag.

Before every interview, spend at least 30 minutes on:

  • The company's website — mission, products, team, culture page
  • Their most recent news on Google (press releases, funding rounds, product launches)
  • Their LinkedIn page and the LinkedIn profiles of the people interviewing you
  • Glassdoor reviews to understand the company culture and common interview questions

Mistake 2: Being Late (or Too Early)

Showing up late is an automatic red flag. It signals poor time management and disrespect for the interviewer's time. Aim to arrive 5–10 minutes early for in-person interviews — not 30 minutes, which creates awkwardness.

For virtual interviews, test your tech the day before: camera, microphone, internet connection, and the meeting link. Log on 2 minutes early, not 15.

Mistake 3: Dressing Inappropriately

When in doubt, dress one level above what you think the company's dress code is. It's far better to be slightly overdressed than underdressed. If you've researched the culture and they're casual, smart casual is still a safe default.

Your appearance also includes: a clean background for video calls, no strong cologne or perfume, and making sure your outfit isn't distracting. First impressions are formed before you say a word.

Mistake 4: Badmouthing a Previous Employer

This is one of the most reliably damaging things you can do in an interview. Even if your last manager was genuinely terrible, speaking negatively about them makes interviewers wonder what you'd say about them if you left.

If asked why you're leaving, use neutral, forward-looking language: "I'm looking for more responsibility," "I want to work in a larger team," or "I've achieved what I set out to achieve there and I'm ready for a new challenge."

Mistake 5: Not Preparing Questions to Ask

"Do you have any questions for us?" is not a formality — it's part of the interview. Candidates who say "No, I think you've covered everything" come across as disengaged or unprepared.

Prepare 3–5 thoughtful questions such as:

  • "What does success look like in this role in the first 90 days?"
  • "What are the biggest challenges someone in this position typically faces?"
  • "How would you describe the team culture?"
  • "What do you enjoy most about working here?"

Mistake 6: Failing to Listen Actively

Many candidates are so focused on what they're going to say next that they stop actually listening to the question. If you don't answer the question that was asked, it signals poor communication skills — regardless of how impressive your answer is in isolation.

If you don't fully understand a question, ask for clarification. It shows confidence and precision, not weakness.

Mistake 7: Rambling Without Structure

Long, unfocused answers test the interviewer's patience and hide your best points. Use the STAR method for behavioural questions: Situation, Task, Action, Result. Keep answers to 90–120 seconds for most questions. If you need more, check the interviewer's engagement before continuing.

"Tell me about a time you handled a difficult client." — Don't say "Where do I begin…" and ramble for 4 minutes. Set the context in one sentence, describe what you did in two, and close with a specific, positive result."

Mistake 8: Being Too Modest or Too Arrogant

Both extremes hurt you. Excessive modesty — "I just got lucky" or "the team did everything really" — makes interviewers doubt your self-awareness and ownership. Arrogance — dismissing colleagues, overstating your role, or making unrealistic claims — makes you impossible to work with.

The sweet spot is confident humility: own your specific contributions clearly, acknowledge your team, and show that you learn from setbacks.

Mistake 9: Not Following Up After the Interview

Fewer than 25% of candidates send a follow-up email after an interview. Doing so puts you in the minority — and makes a genuine impression. Send a brief, personalised thank-you within 24 hours:

  • Thank them for their time
  • Reference something specific from the conversation to show you were engaged
  • Briefly restate your enthusiasm for the role

Keep it under 150 words. The goal is to reinforce a positive impression, not to write another cover letter.

Mistake 10: Performing Instead of Being Authentic

The candidates who consistently perform best in interviews are not the slickest — they're the most genuine. Interviewers are expert at detecting when someone is reciting rehearsed lines versus actually speaking from experience.

Prepare your key stories and examples, but don't memorise a script. Know the themes of what you want to convey and speak naturally. The best version of you in an interview is you — just prepared and focused.