The most common interview mistakes are failing to research the company, not preparing relevant examples, criticising previous employers, underselling yourself or making unsupported claims, talking too much, arriving late, leaving your phone on, showing little enthusiasm, CV discrepancies and sounding desperate. Avoid saying you hate your job, have no weaknesses or have no questions.
Even highly capable professionals make mistakes at interview, and this is the stage that usually decides whether you get an offer. Interview pressure affects experienced candidates too: combined with anticipation and the wish to impress, nerves can lead people to say things they would normally avoid, and one ill-judged comment can undermine an otherwise strong performance.
Most of these errors are avoidable. Drawing on our recruitment experience, here are the ten most common interview mistakes, followed by the phrases and attitudes that most often talk candidates out of a job.
1. Failing to Research the Company
Candidates still arrive without understanding what the organisation does, which immediately suggests they are unprepared or not genuinely interested. Before the interview, research:
- The company's products or services
- Its customers and markets
- Its values and culture
- Recent news or developments
- Its locations and history
- The people interviewing you
You should be able to explain why the organisation interests you and how your experience could support its goals.
2. Not Preparing Relevant Examples
Without preparation, answers become vague and candidates leave remembering the stronger evidence they could have used. Review the job description, identify the essential and desirable criteria, and prepare examples for each important area. The STAR method helps structure your response:
- Situation: explain the context.
- Task: describe your responsibility.
- Action: outline what you did.
- Result: share the outcome.
This keeps your answers relevant and evidence-based.
3. Criticising Previous Employers
This is one of the most familiar pieces of interview advice, yet candidates still get it wrong surprisingly often. However difficult your last role was, avoid speaking negatively about your former manager, colleagues or employer. Even when your concerns are valid, the interviewer has heard only your side of the story, and criticism may make them question:
- Your professionalism
- Your judgement
- How you handle conflict and build relationships
- Whether you take responsibility
- What you might one day say about their organisation
Instead of saying: "My manager was impossible to work with."
Try: "I am looking for a role with clearer communication, broader responsibilities and stronger development opportunities."
Focus on what you want next rather than everything you disliked before.
4. Underselling Yourself or Making Unsupported Claims
An interview is your chance to explain why you should be hired. Excessive modesty stops the employer understanding what you can do, so speak confidently about your strengths, achievements and contribution.
Equally, statements such as "I'm a great leader" or "I'm an excellent communicator" carry little weight without evidence. Support your claims with specifics: cost savings delivered, teams managed, projects completed, compliance improved, customer satisfaction raised, problems resolved.
Instead of saying: "I work well under pressure."
Try: "During a major building-services failure, I coordinated contractors, communicated with senior stakeholders and restored critical operations within the agreed recovery timeframe."
Confidence is not arrogance when it is backed by facts.
5. Talking Too Much
Long, unfocused answers make it hard for the interviewer to find your main point and can lead you into saying something irrelevant or unhelpful. Listen carefully, pause briefly and give a structured response; the STAR method helps prevent rambling. If you are unsure whether you have said enough, ask: "Would you like me to expand on any part of that example?"
6. Arriving Late
Lateness suggests poor preparation or weak time management, and leaves you rushed and unsettled before you start. Plan the route in advance and allow extra time for traffic, public transport delays, parking, finding the right entrance and signing in at reception. Aim to arrive 10 to 15 minutes early and, where practical, do a trial run. If an unavoidable delay occurs, contact the interviewer as soon as possible with an honest update.
7. Leaving Your Mobile Phone On
A phone ringing, vibrating or lighting up with notifications is distracting and looks unprofessional. Switch it off or put it on silent before you enter the building, and keep it off the table unless the interview genuinely requires it. It is a small act that shows respect and keeps you fully present.
8. Showing Too Little Enthusiasm
You do not need to be extrovert, but employers want to see genuine interest. Low energy, closed body language or very short answers can read as a lack of motivation. Show enthusiasm by:
- Maintaining natural eye contact
- Asking thoughtful questions
- Speaking positively about the opportunity
- Explaining why the organisation appeals to you
- Showing interest in the team and its objectives
Preparation makes this easier, because you will know what genuinely interests you about the role.
9. Exaggerating or Creating Discrepancies in Your CV
Your CV often forms the basis of the interview, so know everything in it. Never exaggerate responsibilities, qualifications or achievements, or claim experience you do not have: answers can be tested through follow-up questions, references and qualification checks, and an exposed exaggeration damages your credibility immediately. Before the interview, review your employment dates, job titles, qualifications, training, project details and measurable achievements. Be honest about what you know and show a willingness to learn where your experience is limited.
10. Sounding Desperate
A long job search is frustrating, but do not tell the interviewer that you will accept anything, that you desperately need the job or that several employers have already turned you down. It weakens your negotiating position and makes them question whether you really want their role. Stay positive and focus on why the opportunity suits you, what you can contribute, how it fits your career goals and why the organisation interests you. Enthusiasm is valuable; desperation is not.
What Not to Say in an Interview
Beyond the ten mistakes above, some answers reliably cost candidates the job. Remember that your interviewers may become your colleagues or managers: they are judging whether they would enjoy working with you, not just whether you can do the role.
"I'll have your job"
Employers want candidates who believe in their abilities, but there is a clear line between confidence and arrogance. Asked where you see yourself in five years, "I'll have your job" is unlikely to land as intended. Ambition is valuable when expressed with humility and realism. A stronger answer: "I would like to have developed further within the organisation, taken on greater responsibility and become someone the team can rely on."
"I hate my current job"
Even if it is true, it will not help your application. When asked why you want to move, talk about what attracts you to the new opportunity: greater responsibility, career progression, more challenging work, a different environment, new skills or a better fit with your long-term goals. For example: "I have learned a great deal in my current position, but I am now looking for a role that offers broader responsibilities and greater opportunities for progression." That sounds positive, measured and professional.
Excessive flattery and constant agreement
Genuine enthusiasm is welcome; obvious flattery is not. Forced laughter, exaggerated compliments and agreeing with everything make you look insincere, and interviewers spot it quickly. Respectful disagreement can show confidence, independent thinking and judgement: "I understand that approach. My experience has been slightly different, although I can see why it would work well in this environment." The aim is a professional conversation, not telling the interviewer what you think they want to hear.
"No, I don't have any questions"
Answering "no" suggests a lack of preparation or interest. Prepare several questions about the role's priorities, the team, the management style, current challenges, development opportunities and what success looks like, for example: "What would you expect the successful candidate to achieve within the first six months?" Good questions help you assess the opportunity and show you have taken it seriously. Our guide on why asking questions in a job interview matters has more ideas.
"I don't have any weaknesses"
This rarely sounds confident; it sounds unrealistic or lacking in self-awareness. Choose a genuine development area that is not fundamental to the role and explain what you are doing about it: "Earlier in my career, I sometimes spent too much time perfecting smaller details. I have become much better at prioritising work according to its wider importance and deadlines." That shows honesty, reflection and growth.
Final Thoughts
Strong interview performance is not about perfect, rehearsed answers. It is about preparation, self-awareness and professional communication: research the organisation, prepare strong examples, arrive early, keep answers focused and stay honest and specific.
Avoid criticising previous employers, overstating your abilities or trying too hard to impress. The strongest candidates combine confidence with humility, ambition with realism and enthusiasm with professionalism, and help the employer see that they are prepared, capable and ready to contribute.
For a full checklist of what to do beforehand, read our guide to Facilities Management interview preparation. And for a lighter look at what can go wrong, see our 20 real-life interview stories.
Talk to Maxwell Stephens
If you are hiring in Facilities Management, talk to our team about what the market currently expects. If you are an FM professional weighing up your next move, the Facilities Management jobs we are handling span the public, private and not-for-profit sectors.
