3 Mistakes Candidates Make To Ruin Their Next Job Interview

Job Interviews are a serious affair.

A moment that can define your future career and life.

Yet, some candidates take it for granted.

They leave their next job opportunity to chance.

There are many reasons why candidates get rejected, but there are the common ones I have witnessed firsthand.

You must avoid these events like a disease if invited for an interview.

1 – Turning Up Late

The panel may not forget if you attend a job interview late.

First impressions, they say, last longer.

You would need to be exceptional to overturn the initial disappointments.

I once sat on an interview panel for a top analyst role.

We had this candidate lined up for this interview. It was an online interview. At the start of the interview, we didn’t see this candidate join.

Two minutes passed, 10 minutes passed, and still nothing.

We rang the candidate to find out what was going on. The candidate apologised that they would join shortly and joined five minutes later.

There was no prior communication about the coming later. Nothing. The candidate just turned up with a smile like Santa bearing gifts on Christmas day.

I was surprised.

Of course, that first impression ruined the entire experience. It would take a miracle for the candidate to land the role. As expected, they didn’t get the job because the interview was below par.

If you are ever going to interview, you must prepare to come in early. Yes, life happens, but that’s why you have your mobile phone and should communicate.

  • Try not to run late for an interview. You can do a practice run to the interview venue a day before or so to familiarise yourself with the route.
  • Check your tech if attending online.
  • Set multiple reminders or alarms or inform a friend or family member so they can remind you if possible.
  • Sometimes, life happens. Always communicate if you are running late for an interview.
  • Communicating shows you respect the panel as you would yourself. 


2 – When It’s obvious to the panel you didn’t prepare

Not preparing for an interview might ruin your chances of landing the role.

I recently sat with a panel chair interviewing for a senior role.

They had to interview two to 3 potential candidates for the role.

The interview went well on average; however, there was just one thing that disgusted the panel chair – the lack of preparation of one of the candidates.

The hiring manager said it was so clear from the first question that the candidate did not prepare.

Their responses lacked direction and depth and could not explain why a candidate would show up for an interview without preparation,

The candidate did not get the job, and they would probably not land any other roles within the same team soon.

Always prepare for your interview.


  • It shows you are genuinely interested in the role.
  • It shows you are ready to move to the next level.
  • It shows you respect the panel’s time. 

3 – Fail to attempt an interview task

I once sat in a panel where candidates were required to complete an assessment task before the interview.

The candidates were meant to present and speak about their analysis during the interview.

They were not required to submit it prior.

This candidate joined the interview, and the panel asked to show the presentation, but they hadn’t completed it.

It was strange to the panel chair.

The interview barely lasted half an hour because the candidate did not complete their task.


  • Always complete your assessment task before the interview
  • You can ask for an extension if you need more time.
  • Not completing a task shows you aren’t interested in the role and may not get hired.

Closing Thoughts

Interviews can be an excellent experience if you are prepared for them.

Don’t get automatically disqualified because you showed up late without notice, did not prepare for an interview or did not complete an assessment task.

Put in your best in your next job interview.

Don’t shoot yourself in the foot.

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