How do you deal with interview burnout, as an interviewer?

First, remember that you're doing an incredibly valuable service for your team. The time spent finding and vetting new people will have an impact larger than most other direct contributions. Your team thanks you (or should!)

Second, remember that asking the same questions is the only useful way to get a read on people. Without properly-calibrated questions, you have no basis to know whether a particular question is good or bad.

Third, try to improve your "read":

* For "soft interview" questions, instead of asking questions and recording the responses, look for specific truths that you want to discover. Example: "Is this person a jerk?" You might be able to uncover this with one question or it might take several to dig in deeper. Choose calibrated questions from a pool as you go through the conversation and focus on discovering the questions which give the best signal. Try out different wording of the same basic question and see if you get different responses. Become a student of human nature... if a fellow interviewer notices something you didn't, ask yourself why and try to improve.

* For "coding challenge" interviews, focus on growing your ability to coax the best possible performance out of your candidate. Are they nervous? Learn ways to set them at ease. Brain freeze? Try to find the best way to get them un-stuck without giving away the solution. Your goal is to answer the question "Is this person competent?" as quickly and accurately as possible, ideally with a read on seniority level, while ensuring that the candidate feels successful. Even a clear No Hire candidate should walk away thinking that they are ok (as a person, if not in their skill level), you are ok, your company is fantastic, and they wish they could work there.

Fourth, give yourself a break. Understand that 3 interviews / day is a LOT. The context is artificial, and you're multitasking the entire time... asking questions, listening to responses, evaluating, guiding, recording, vetting, selling. I personally find it difficult to do more than 1-2 per day. Hopefully this situation is temporary. Don't be afraid to set boundaries and call in help if you can.

Some suggestions:

1. Raise the bar for previous step in the process. How many candidates are you rejecting? Is there a common thread between rejected candidates that can be identified earlier without a developer (e.g. phone screen with HR, automated FooBar test)?

2. Spread the load. Train other people to interview.

3. Align on hiring goals. Do you need to be interviewing this much, how many open positions are left?

I used to do it a lot at a FAANG and another time for an agency, and 1 per week was often. I had a track record of good hires apparently and they still only asked me to do it once a week at most. So I think you're doing it far too often.

As for advice on how to improve it-- my best advice is to see it as talking shop with a fellow coder. Let your guard down, discuss areas you both overlap. At least half the time I would need to be extremely patient while they attempted to contribute, but it's what you do as an interviewer to attempt to coax out the best in a candidate, similar to what _ah said in their response. Sometimes they come through sometimes not, which is the point of the interview of course! Good luck, and have fun meeting some new people. I've kept in touch with some, have learned a lot from others, and seen some around the office, I always enjoyed that aspect of it as well.