I had several similar experiences through and after college. One in particular was while I was still in school, they had asked a question relative to performance when using views in an SQL database, and my answer wasn't satisfactory to them. Despite the interview going well up until that point, you could feel the tone shift immediately after, like they were just asking the rest of their questions as a formality and wanted me out of there as quick as possible. Didn't get called for a follow up, of course. Found out later that place was actually preying on foreign-based students (who received funding from the university to cover their out-of-state tuition difference if they worked up to 20 hours / week max for a company associated with campus) by making them work 60-80 hour weeks along side school and threatening to fire them if they told anyone, which would cause them to lose their funding and likely have to drop out / move back to their home country.
I received offers from several others, some never called back. Ended up turning all those down though, as I had an interview with someone who helped step through the few mistakes I made as a learning process during the interview. One particular question I remember was basically building front-end components with Javascript, and my example had a loop with a write call in it. He mentioned he would compile the markup in the loop, then write it after it was finished, and asked why that would be better or worse. Had to think on it for a minute, but came up with a trade-off between more memory usage but less DOM writes, resulting in faster rendering. Worked that into the next coding example too, since it was similar but more complex. After the interview, when they called to schedule a follow up interview before I even made it home, I realized he was more concerned about whether I would ask for help, learn, and not make the same mistakes again. Worked there, learned a ton, became a senior dev just few years out of college, now I manage a suite of products for my current company. I don't think I would have gotten that kind of opportunity had I not had that first manager and job, so I strive to emulate that in my interviews.
One of my favorite questions is something like "describe a crisis that occurred and the steps you took to resolve it," and give an example of one of my many stories of pushing bad code to production, having a server crash, etc, etc. I love the question because it involves no coding, no memorization, no regurgitating of info. Instead, it resolves around the person being a hero, which in my experience usually gets them relaxed, comfortable, and talking. You also learn a lot about their thought process: How did they first notice the issue? What was their process for triaging it? How did they debug it? If something involved in it was out of their wheelhouse did they go to someone else more experienced for help, or did they search for similar problems online to try and narrow it down? Did they delegate tasks if the workload was too high for them? Once it was fixed what was the procedure it went through for testing / verification? Did you monitor the issue afterwards to make sure it didn't come back? Once it was deployed, did you search for similar issues affecting your other systems? Did it ever come up again in new code and you were able to identify it before it was deployed?
Obviously not all of these will apply to everyone, but the open-endedness of the question means you can probe a bit here and there throughout their story and gain a ton of relevant insight. And most importantly, it answers the question of "when things get tough, can you keep a cool head and think critically?" I can teach code, data structures, algorithms, whatever, to anyone. But the difference between someone who is always trying to learn and grow, takes initiative, asks for help, etc, and someone who just wants to do the bare minimum is night and day.
Side benefit is this usually takes up several minutes of an interview so they can't be used on BS questions like the one you mentioned.
I received offers from several others, some never called back. Ended up turning all those down though, as I had an interview with someone who helped step through the few mistakes I made as a learning process during the interview. One particular question I remember was basically building front-end components with Javascript, and my example had a loop with a write call in it. He mentioned he would compile the markup in the loop, then write it after it was finished, and asked why that would be better or worse. Had to think on it for a minute, but came up with a trade-off between more memory usage but less DOM writes, resulting in faster rendering. Worked that into the next coding example too, since it was similar but more complex. After the interview, when they called to schedule a follow up interview before I even made it home, I realized he was more concerned about whether I would ask for help, learn, and not make the same mistakes again. Worked there, learned a ton, became a senior dev just few years out of college, now I manage a suite of products for my current company. I don't think I would have gotten that kind of opportunity had I not had that first manager and job, so I strive to emulate that in my interviews.
One of my favorite questions is something like "describe a crisis that occurred and the steps you took to resolve it," and give an example of one of my many stories of pushing bad code to production, having a server crash, etc, etc. I love the question because it involves no coding, no memorization, no regurgitating of info. Instead, it resolves around the person being a hero, which in my experience usually gets them relaxed, comfortable, and talking. You also learn a lot about their thought process: How did they first notice the issue? What was their process for triaging it? How did they debug it? If something involved in it was out of their wheelhouse did they go to someone else more experienced for help, or did they search for similar problems online to try and narrow it down? Did they delegate tasks if the workload was too high for them? Once it was fixed what was the procedure it went through for testing / verification? Did you monitor the issue afterwards to make sure it didn't come back? Once it was deployed, did you search for similar issues affecting your other systems? Did it ever come up again in new code and you were able to identify it before it was deployed?
Obviously not all of these will apply to everyone, but the open-endedness of the question means you can probe a bit here and there throughout their story and gain a ton of relevant insight. And most importantly, it answers the question of "when things get tough, can you keep a cool head and think critically?" I can teach code, data structures, algorithms, whatever, to anyone. But the difference between someone who is always trying to learn and grow, takes initiative, asks for help, etc, and someone who just wants to do the bare minimum is night and day.
Side benefit is this usually takes up several minutes of an interview so they can't be used on BS questions like the one you mentioned.