Keeping Interviews on Schedule - Effective Interviewing

Keep an interview on schedule

In my previous post on interviewing TPMs, there was a note in the comments about keeping interviews on schedule.  This isn’t the first time people have asked about this topic though, since it is a challenge for any interviewer.

• You want to make sure candidates have a great experience interviewing.
• The candidate deserves a fair shot, so you want to make sure they have a chance to tackle the problem (and this can be a challenge, because some great candidates just aren’t good at some questions)
• You want to cover a lot of material so you can feel confident in your hire/no hire decision.

Like most things in life, the key to a successful interview is to prepare ahead of time and have a good plan.  I wrote another post on how to prepare for interviews, and taking these steps certainly help ensure you cover all of your desired material, and ideally keep an interview on schedule.   So assuming you have prepared, here are some tips and pointers to help you make the most of the interview (and still provide a good experience for the candidate).

1. Prepare, have a plan and agenda.  This was mentioned above, but worth repeating since it is the one thing that is easy to do but often forgotten or neglected.  Having a clear agenda and timeline for the interview is paramount for covering all of the material.  Make a list of the questions you plan to ask (bonus points for noting the goal and competencies you are testing with each question) and in what order you plan to ask them.  My 60 minute agenda is usually something like: background questions 5-10mins, problem solving/coding question 10-20 mins, system design question 10-15 mins, culture questions 5-10mins, and questions they have 5-10 mins.
2. Ask familiar questions and know how long they should take to complete.  The best questions are one you have asked to many candidates and have a good bar on what is a good answer, and also identifying places where they might get stuck.   You should definitely try solving the problem yourself in the same environment (white board, pen and paper, or computer) and note how long it takes you to complete.  Then as you ask the same questions over and over (which is good practice to calibrate your bar for hiring) keep track of how long different candidates take to answer.  I keep a spreadsheet of my interview questions and will make notes about different questions (including good follow up questions, timing, hints, and sometimes solutions); I have maintained this for years and add to it when I interview places or hear good questions from others.
3. Know how to give good hints and where candidates may get stuck.  Giving good hints and helping candidates through a problem collaboratively is typically what sets apart good vs. great interviewers.  And knowing how to get through the problem, and where candidates may get stuck, is also very helpful to ensure the interview follows your planned schedule.  Of course if you are just starting to interview, this isn’t something that will just happen, so for teams that I am on, I like to have a rule that you never ask a question unless you have tried it yourself, or asked it to one of your teammates – that way you have at least one data point and aren’t going in blind.
4. Have a clock or watch in the room (ideally not your cell phone).  If timing is part of interview success making sure it is easy to keep time is important.  Therefore scope out the room ahead of time, is there a clock you can see?  Make sure you position yourself so you can glance at it without being distracting or awkward.  I would advise against using your cell phone, because most of them you have to push a button to see the time, and just having your phone in the room can be distracting.  I know it would be easy for me to check my phone for the time and then be distracted by the text message that came in earlier (and is right there on the center of the screen!).  Be respectful to the candidate and don’t have your phone on (or if you are on call and have to have your phone on for some reason, let the candidate know at the beginning of the interview so they understand if an interruption occurs) and don’t look at it if you don’t have to do so.  And if there isn’t a clock in the room, get a watch and put it on your wrist or in your pocket.
5. Don’t be afraid to interrupt.  This can be a hard one to get over, since we all want candidates to do well and want to give them time, however, if you only ask one question and the candidate takes forever it could do both you and the candidate a disservice – they only get one shot, and you only get one data point.  This means if a question is going the wrong way, or you have reached your planned time limit, interrupt the candidate and let them know you are going to move on.  Some of my favorite ways to do this are using statements like: “I think I see where you are headed; so in the interest of time let’s move onto the next questions so you have a chance to try the other material as well”, or “I think we are far enough on this problem, since I have a lot of questions let’s move on”.  In the event the candidate is doing poorly you can say, “I think I hit on something you don’t know – and if we didn’t ask things you didn’t know I wouldn’t be doing my job.  Let’s move onto the next question and explore another area.”  This last statement is both encouraging and keeps the schedule (and it is important to be encouraging because you don’t want candidates to fall into a downward spiral sabotaging their chances).  Just don't be afraid to be honest and authentic, the candidate will understand.
6. Interrupt, and tell them you can come back to it.  I have also found that if a candidate gets stuck on a specific problem and I am worried about sticking to the schedule, I will interrupt them, and let them know I want to cover other material, but if we get through it fast enough we can come back at the end.  On the phone, I also let them know they can email me a solution after the fact.  This makes them feel better about that problem (knowing there is a second chance), and at the same time allows you to move forward to cover the rest of your planned material.
7. Let the candidate know you have a plan and set of questions to cover.  By starting the interview off with a statement telling the candidate you have a schedule and planned material, they will know and understand if you need to interrupt them or cut a question short later on in the interview.  I start every interview with a statement like: “I am so excited I got to talk with you today.  If you don’t mind I am going to jump right in since I have an agenda and a lot of ground to cover.  But don’t worry, I will try to leave time at the end for questions, I just want to make sure you have ample time on the problems.”
8. Change directions if the conversation/problem is not productive.  Tying in with point #5 about interrupting if the candidate clearly doesn’t know how to solve the question you are asking (you planned to ask about an architecture question and it is clear they never had insight into how their software was run on the website – and this can happen in really big companies), then don’t feel bad about changing direction and cutting the candidate off. To make this work well…
9. Have a few backup questions in your pocket.  Sometimes I use back up questions as ones that are less road tested or perhaps at a different level than I had pegged the candidate.  Plan to have extra hard ones (if the candidate does really well and blows through all your material), easy ones (if the candidate is doing poorly and you can’t end early), and non-technical ones (since sometimes you just want to know more about culture if you feel confident in your technical/skill assessment).  This was you will be able to adapt and make the most of your interviewing time (because as a candidate, it sucks have 20 minutes left in the interview and the interviewer expects you to fill that time with questions – and yes, this happened to me before).

And one thing worth calling out is:Don’t be afraid to print out and bring in notes.No one will be offended that you took the time to review his or her resume and prepare for your interview.  It is okay to bring in your plan, list of questions, and backup questions.  I have done over 650 SDE interviews at this point in my career and still bring in notes to my interviews :)Do you have any other tips or ideas?   If so, please leave them in the comments as I am always looking for ways to improve my interviewing too!