Warning: Interview mistakes that could cost you the job

The job interview is your single best chance to secure a role, yet even highly qualified professionals make simple, fixable mistakes that can immediately detract from their candidacy. In a competitive job market, attention to detail and professional tact are non-negotiable. We spoke with Elizha Corpus, an HR Consultant specializes on leadership development, who shares the most critical errors that derail job seekers and provides strategic advice on how to navigate communication hurdles common in the local professional landscape. 

Mistake #1: Being Late 

Even with persistent challenges like heavy traffic, lateness signals a lack of respect for the hiring manager’s time or low interest in the role.  

Do this instead: Plan Ahead 

Properly plan and consider other factors that might affect your punctuality. “Punctuality communicates foresight and professionalism. The safe rule is to arrive at least 20–30 minutes early for a physical interview, factoring in traffic and security checks,” says Corpus.  

For online interviews, log in 15 to 20 minutes beforehand to account for any tech checks. Being early shows you value the opportunity and can manage external challenges, especially in high-stakes situations. 

Mistake #2: Looking Untidy 

Professionalism goes beyond the clothes you wear. Hiring managers pay close attention to the neatness and intentionality in your presentation.  

“Neglecting small details in grooming or the presentation of your interview space.” Corpus points out as a mistake.  

Do this instead: Dress accordingly 

“Look presentable by ensuring tidy hair, clean shoes, pressed clothes, and minimal scent. For virtual interviews, choose a well-lit spot with a clean, uncluttered background. If using a virtual background, ensure your lighting is adjusted so you can be seen clearly. These details show you are prepared and taking the interview seriously.” 

Mistake #3: Overselling or Rambling 

Many professionals try to avoid sounding mayabang (boastful) by either softening their achievements or over-explaining out of excessive humility. This ironically leads to answers that sound unfocused or uncertain. 

“The usual mistakes are using hedging language (e.g., “I think I tried my best…”) or rambling to fill silence.” says Corpus.  

Do this instead: Be concise and specific  

“Let the facts do the talking.” says Corpus. Focus on the impact and results of your achievements. Instead of saying: "I think I tried my best and did what I could to lead that team." Say something like, “I led a team of five and we exceeded our targets by 20%.” 

Ms. Corpus affirms: "It’s not bragging when it’s true and relevant to the role." 

Mistake #4: Speaking Negatively About Past Employers 

Out of a desire for honesty, candidates often focus on the negative reasons they left their last job. However, speaking poorly about a former boss or company can make hiring managers question your emotional maturity and future loyalty. “It’s focusing on frustrations or criticizing a previous manager’s leadership style,” says Corpus.  

Do this instead: Be tactful and neutral  

Corpus says that you can reframe the reason for leaving into a positive statement about your future career goals. “Instead of: ‘I left because there was no career growth there.’ You can say, ‘I’m looking for a role where I can continue developing my leadership skills. Or instead of ‘I didn't get along with my boss’s leadership style.’ You can say, ‘I learned a lot from my last team, and now I’m looking for a workplace that encourages open communication and collaboration.’ 

This keeps the tone forward-looking and mature. 

Mistake #5: Lack of Company Research 

Failing to conduct thorough research on the company, its mission, and its values is a common mistake that is easily exposed when the interviewer asks, "What do you know about our company?" It’s having a generic understanding of the company that shows you are "job-hunting" rather than pursuing a specific opportunity. 

Do this instead: Read through the company’s profile  

Here’s Corpus advice: “Take the extra time to read up on the company’s goals and values. When you reference their mission or current projects during the interview, you demonstrate malasakit (genuine concern and ownership). Showing that you invested time and energy signals maturity and preparation—great indicators of how you might work in the future.”  

Mistake #6:Failing to Ask Questions 

Not asking questions at the end of an interview is a common error that can signal disinterest or a lack of engagement with the role's details.  Saying, "No, I don't have any questions," when the interviewer opens the floor. 

Do this instead: Do your research  

“Always prepare a few thoughtful questions that demonstrate your research and long-term interest. Questions about team structure, performance expectations, or company evolution are excellent ways to show engagement.”