Hiring great tech talent is the foundation for strong teams. The importance of fine-tuning the interview process and the quality of the interview loops should be of great concern for all hiring managers and organizations. Screening candidates is a very important aspect of any interview.
In a world where a full technical interview can cost your team 4 to 10 man-hours, mastering the art of screening candidates is key to reduce costs, scale hiring efforts, and quickly sift through many promising resumes.
The success of any screening methodology is measurable by the rate of candidates that pass the full interview after they pass the screening itself. That is all you can measure. It is also theoretically measurable by the inverse rate of candidates you screened out, that would have otherwise been successful in a full round of interviews. Unfortunately, by definition, you can’t measure that because you prevented those candidates from proving themselves.
Years ago I used to do phone screenings. Doing phone screenings had some practical advantages, but unfortunately, many candidates who passed them with flying colors were not able to pass the full technical interview loop. In many cases, they were not even close.
Convinced that perhaps I was a “bad phone screener”, I asked some of my senior staff to do that for me, but results were very similar. I tried different types of phone screenings and played with many variables, but in general, the results were poor at best.
At some point, a strong pattern emerged:
When an insufficient screening is done, the candidate success during the resulting multi-hour in-person & on-site interview loop is easily predicted by the results of the very first one or two hours of the loop.
Armed with this observation I started interrupting interview loops early if things didn’t go well. The rationale was that I was saving time to the team and the candidate.
That did save time, but it was still not a satisfactory situation. It cost the candidate, my team, and HR many man-hours of wasted time to organize, book and perform parts of the interview. Moreover, it left everyone unsatisfied by the experience, especially the candidate.
(When you are invited for a multi-hour interview loop and you are asked to leave after one or two hours, it leaves you with a bitter taste in your mouth.)
Additionally, I had this lingering feeling that phone screenings were not only bringing the wrong candidates in for interviews; most likely, they were also blocking possible solid candidates from proving themselves, which was even more of a problem for me, and unfair to the candidates.
With that in mind, I switched to in-person and on-site screenings. My success rate soared, my team made many successful hires, and I never went back to phone screenings.
In the process, I also developed a few simple rules that I apply to most technical screenings, and that significantly improved my hit rate. I am going to share those with you:
Candidate Screening, General Rules of Thumb
- Put the candidate at ease.
- Throughout the screening, make sure the candidate becomes a fan of the company, even if they do poorly.
- For technical positions, give at least one whiteboard exercise.
- Let the candidate think and speak at least 80% of the time.
- Don’t let the candidate rumble for too long if you know that what they are saying does not help you make a decision.
- Answer all the questions honestly, but succinctly.
- At the end of the screening, inform them in great details what is going to happen next. If they didn’t do well, and there is not going to be the next step, let them know immediately.
- After the screening ensure that the follow-up, if any, goes exactly as you outlined.
Remember that the purpose of a screening is to decide if the candidate should come in for a more in-depth interview with the team. You are not deciding to hire them at that point; you are deciding if you want to invest time and effort in exploring if they are a good match for one of the available positions and the company.
How do you decide if a candidate is a right person to come in for a full interview? The answer is going to depend on the position, the company, and the culture, and often is just a “gut feeling.” That said, I’ll share with you some of my rules of thumb applicable to technical positions.
The screening didn’t go well if, after at least 20 minutes, I am 80% sure of anyone of the following points:
- The candidate makes me uneasy.
- The candidate cannot grasp the solution of the problems given, meaning that they cannot resolve a problem and they cannot understand the solution when I explain it to them.
- The candidate cannot come up with more than two questions about the position, the company, the mission, the product, the team, or the culture.
- The candidate tends to confidently give wrong answers.
- The candidate tends to answer seemingly unrelated questions to what I asked.
- The candidate is a “messy thinker” and cannot stay on a stable line of thinking.
- The candidate tends to get irritated or tends to irritate me.
- The candidate won’t be able to pass a formal interview loop with members of my team.
- The candidate appears to have dogmatic positions that seem to be in contrast with the culture and values of the company.
In all those cases the candidate is probably not a good fit, and I do not ask them to come back for a longer and more formal interview.
With a more solid screening methodology, the result of the first hour or two of the full interview loop is no longer a leading indicator of the candidate success during the interview. Since the quality of the candidates admitted to the interview increases, the 4-10 man-hours spent doing it are much more valuable and provide a positive Return on investment. Used as a rudimentary gauge of an investment's profitability..