5 Most Common Mistakes When Interviewing Software Engineers

When it comes to interviewing software engineers, I've been on both sides of the table. Through countless interviews, both as a co-interviewer and an interviewee, I've witnessed a wide range of techniques, some successful and others less so. Here, I want to share some common pitfalls that interviewers often fall into, which can hamper finding the right candidate for the role. This guide is particularly useful for engineering managers, tech leads, or anyone involved in interviewing software engineers.

1. Focusing Too Much on Textbook Questions

One of the most frequent mistakes I've observed is an over-reliance on textbook questions. Questions like "Define encapsulation" or "What is polymorphism?" are not only uninspiring but also outdated in the era of Google and AI-enhanced coding tools. Interviews should aim to understand a candidate's ability to solve real-world problems, not just their capacity to recite definitions.

A better approach

By focusing on practical applications and scenario-based challenges, interviewers can better assess how a candidate thinks on their feet, applies knowledge to new situations, and collaborates with others to find solutions. This approach not only makes the interview more dynamic but also aligns more closely with the demands of modern software development environments.

Furthermore, incorporating open-ended questions that encourage candidates to discuss past projects or real-life scenarios where they applied specific technologies or methodologies can provide deeper insights into their expertise and adaptability. For instance, asking a candidate to describe a complex software problem they solved or a time they optimized a system can reveal much about their critical thinking, problem-solving skills, and ability to drive results under pressure.

These discussions can also highlight a candidate's communication skills and ability to articulate technical concepts clearly and effectively, which are crucial for team-based projects and leadership roles. By shifting the focus from theoretical knowledge to practical expertise and soft skills, interviewers can gain a more comprehensive understanding of a candidate's overall fit for the position and the company culture.

2. Evaluating Candidates Based on Your Strengths

A significant misstep that interviewers often make is assessing candidates based on their own strengths instead of uncovering the unique strengths that each candidate might bring to the table. This approach can skew the evaluation process and result in a homogeneous team that mirrors the skills of the interviewer rather than complements them.

The risk of this bias is that it can create a team environment where diversity of thought, experience, and problem-solving skills are limited. Diversity in skills and perspectives is essential for fostering innovation and effectively addressing a wide array of challenges. When interviewers project their own competencies as a benchmark, they may overlook candidates who possess different but equally valuable abilities that could enhance team performance and lead to novel solutions.

A better approach

To avoid this pitfall, interviewers should consciously broaden their criteria and consider what unique contributions a candidate can make. This involves recognizing and valuing different skill sets, experiences, and viewpoints during the hiring process. Structuring interviews to explore how candidates have solved problems in unique ways or contributed differently to projects can provide insights into their individual strengths and how they might diversify the existing team's capabilities.

Additionally, using a diverse panel of interviewers can help balance out individual biases and ensure a more comprehensive evaluation of each candidate's unique talents and potential contributions. This collaborative approach to interviewing not only helps in selecting the right candidate but also in building a team that is well-equipped to innovate and adapt in a rapidly changing tech landscape.

3. Neglecting Soft Skills and Team Dynamics

In software development, while technical skills are essential, soft skills are equally critical and often overlooked during interviews. Skills such as teamwork, communication, and adaptability are crucial as they largely determine how well a candidate will integrate into and adapt to your team's culture.

A common and significant oversight is neglecting to assess how a candidate's personal attributes might affect team dynamics. For instance, a strong ego, which is not uncommon among developers who are highly skilled or have specialized knowledge, can sometimes disrupt team harmony and collaboration. While confidence is valuable, an overbearing ego can lead to conflicts, hinder cooperation, and impede collective growth.

It's crucial to evaluate how candidates interact with others and respond to collaboration and flexibility during the interview process. Exploring their past team experiences, challenges in group settings, and their approach to feedback can offer deep insights into their ability to function effectively within a team. Role-playing situations or group interviews can also provide important cues about a candidate’s interpersonal skills and ego, showcasing how they manage real-time interactions with potential colleagues.

By focusing on these aspects, interviewers can better predict a candidate’s potential to positively contribute to the team's success and create a balanced, cohesive workplace environment.

4. Unprofessional Behavior

It may seem obvious, but it's painfully common to encounter unprofessional behavior during interviews. From my own experiences, I have witnessed interviewers who were rude, condescending, or simply appeared annoyed, which not only undermines the professionalism expected but also significantly impacts a candidate's experience. Such behavior can tarnish both the overall perception of the company and the personal reputation of the interviewer.

Maintaining professionalism in interviews is critical as it mirrors the company's overall attitude towards its employees and its approach to business practices. Candidates often view their interaction with the interviewer as a direct indication of the company's work culture. Thus, it is essential for interviewers to always conduct themselves with courtesy, punctuality, and attentiveness.

These qualities not only respect the candidate and their time but also establish the standards of interaction they can expect if they join the company. By consistently demonstrating high standards of professionalism, organizations can boost their appeal to potential employees and reinforce a culture that values respect and excellence.

5. Lack of Preparation

Last but not least, lack of preparation from interviewers can significantly disrupt the interview process, potentially leading to a disorganized session that reflects poorly on the company's professionalism. Proper preparation is crucial as it shows respect for the candidate's time and indicates that the organization values diligence and thoroughness.

Preparing for an interview means more than just reviewing the candidate’s resume; it involves understanding the specific requirements of the role and developing targeted questions that probe these areas effectively. This preparation allows the interviewer to conduct a focused and efficient assessment, ensuring that both the candidate and the company can determine if there is a good mutual fit. A well-prepared interviewer can also competently answer any questions the candidate might have, further enhancing the company's image as an employer of choice.


In conclusion, effectively interviewing software engineers goes beyond assessing technical skills and involves a holistic view of candidates, including their soft skills, unique strengths, and how they fit within the team dynamics. Avoiding common pitfalls such as focusing on textbook questions, preparing inadequately, and neglecting soft skills, or displaying unprofessional behavior, is crucial. These mistakes not only hinder the selection of the right candidate but also impact the reputation of your company. By refining the interview process and embracing a more thoughtful and comprehensive approach, organizations can enhance both the quality of their hires and their overall workplace environment.

Wei-Ming Thor

I create practical guides on Software Engineering, Data Science, and Machine Learning.


Full-stack engineer who builds web and mobile apps. Now, exploring Machine Learning and Data Engineering. Read more

Writing unmaintainable code since 2010.


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