Unless the interviewer has totally lost sight of the purpose of the interview, they’d recognise a candidate starting at an offset from 50 as an instant pass.
I think like 70% of interviews I ever had were like they were there to prove how smart they are and how stupid I am. I suppose most likely to make me feel stupid and accept lowball offer.
One of the worst interviews I ever had was just like that.
Often times, the "gotcha" part is just dumb and nonsensical, yet gives the interviewer(s) a sense of misguided (false) superiority, and wastes everyone's time. I would venture to say that 99% of the time it's complete un-indicative of how effective the candidate would be in the role.
Referring to my aforementioned bad interview - the question, after all the technical stuff had been cleared (this was for a junior frontend dev role) - they asked "imagine a car is broken and not running. how would you go about figuring out how to fix it?". Being someone whose brother and father enjoyed fixing cars, I asked every question about the problem with the car - how it was used, what sort of car it was, what the issue with the car was, what prior problems the car had, etc. I got a bunch of useless answers. After I exhausted all my questions, the interviewers told me I had failed. Why? One interview brought out a tiny hotwheels car with a missing wheel out of his pocket, and proclaimed to say "you didn't ask if it was a real car, it's a toy car, of fucking course it's not supposed to run like a real car!" while laughing hysterically. How on earth does that indicate if a junior frontend dev can do their job or not? Stupid.
I had an interview at a major tech company with a similar thing, for a more managerial role.
The question was to estimate how many vacuum cleaners there were in the city we were in.
Fine, I did some estimation of how many vacuum cleaners per household and per office, across how many households and offices. Standard stuff.
Then the guy starts laughing and saying I'd failed because I didn't include discarded vacuum cleaners in landfills. Or the vacuum suction devices they put in your mouth at the dentist's office. And so forth. And then had to spend the next five minutes listening to him "teach me" how not to make assumptions. So I acted all polite and tried to fake "oh gosh thank you so much for enlightening me!"
Shockingly, I got the job, which required unanimous approval from all interviewers. Never met him again, and to this day I still have no idea whether this was supposed to be a test of estimation (which was easy to pass), a test of not making assumptions (which is dumb, but OK fine I failed), or a test of being appropriately professional and smiling in the face of complete bullshit (which I'd say I passed with flying colors).
I mean, in my professional life I've certainly had my fair share of customers and managers and coworkers who spout bullshit and you really do just have to lie with a smile and say "oh my gosh you're so right thank you for explaining that, I appreciate you so much!" Where you need to make them feel smart.
On the other hand, I just don't think he was thinking that far ahead.
Is the landfill actually 'in' the city, or in a rural area outside the city limits?
I had a similar interview years ago - something like "how many windows are there on houses in our town?". Wasn't quite that, but I asked up front if "houses" meant just physical standalone houses, or if they meant living spaces, including apartments/dorms, etc. I got clarification, gave some estimate with some reasoning, and was then told I was the only person of the 8 they'd interviewed that had asked any clarifying question at all, which apparently impressed them enough to make an offer.
Yes, I have used questions like this before for junior roles and the notes for the interview were something like:
- Asked/did not ask clarifying questions
- Did/did not (or could not, on prompting) verbally walk through their reasoning
- Could/could not articulate which assumptions they felt were most important/why
Nothing about the actual content of the question itself, or if your answer was approximately correct (I usually did not know even the ballpark of the correct answer myself). I will say I did sometimes write down if candidates make comically bad assumptions. Like assuming the population of the USA was 1 Billion people. It's a fine line on what is "comically bad" but like, if you are interviewing for a startup of 20 people and you use $20B/year as the revenue assumption with no wink. That's a red flag. Lmao.
> Like assuming the population of the USA was 1 Billion people.
Is that comically bad? It's only like three times too much (if you're using the American, 10^9 billion), but we'd accept a much greater margin of error in some other assumptions (like in the classic 'how many Piano tuners are in the city', I think an assumption of 1-in-30 or 1-in-300 households having a piano (that would need tuning) all sound like they could be true!)
Totally my personal opinion, but not knowing the approximate population of the country you live in betrays a pretty serious lack of curiosity about the world. Obviously a judgement call on how far off is "far off", but it just gives a funny feeling, you know?
True, but in the context of making a ‘finger in the air’ calculation, 1 billion or 100 million (approximating to the nearest power of ten) should be “good enough’.
And if you’re interviewing, consider that for a decent proportion of people it may not be the country they live in (at least at the time you’re asking the question).
Yeah, I think there's a possible pitfall with using this as an interview technique though.
When you're in a real situation with a customer or user, you ask tons of questions. You use a lot of common sense to figure out what they really want, what's actually important, etc.
But often times these interview questions -- like how many vacuum cleaners in a city -- don't need any further questions asked. The idea that you'd count vacuum cleaners in landfills, or dental suction devices, is just silly. In real life, if someone wanted to know about the vacuum cleaners in landfills too, they'd tell you in the first place.
If an interviewer wants to see if someone can ask clarifying questions, they'd better come up with a scenario where it would make sense to ask them in a normal conversation. Scenarios that are genuinely ambiguous to anyone with common sense.
Otherwise interviews become this weird cargo-cult thing where you have to learn that interviewers present common-sense clear questions, but you have to ask silly clarification questions that you wouldn't in real life, just so somebody can check a box that you asked questions.
Yeah I mean the vacuum landfill thing is stupid. The point was never to try to trip people up, there's no wrong answer (or question), just find out if they could recognize ambuiguity. "Let's try to estimate the amount of pet food sold each year in the USA." -> "Dogs and cats too?", "In terms of dollars or pounds of food?" type of stuff. This was for analyst roles - basically your whole job would be something similar to this where you're asked ambiguous questions and you need to translate that into a semi-rigorous analysis, infer intent, etc. I hate to say it but if you didn't realize that going into the interview, you were probably not a good fit as an analyst in the first place!
I’ve seen customers wanting X and assuming that you should know that X comes with A and B because everyone in their business knows that. But you implement only X with A because you made your own assumptions and did not ask. So you missed the deadline and customer that’s it.
> How on earth does that indicate if a junior frontend dev can do their job or not?
Playing devil's advocate, maybe a junior frontend dev that doesn't trust that they understand what someone is asking for and pushes back on bits that should be obvious will perform better (in some contexts?) than one that doesn't.
For a junior role in particular, though, it really doesn't seem like that should be the threshold and it sounds like it was delivered poorly on top of that.
I hear what you’re saying, but really, this is a stupid question and a waste of everyone’s time. Instead you could give a real big report that has insufficient information or that contains a red herring to an improper assumption. The interviewer could then measure if the candidate properly pushed back, exposed an improper assumption and asked relevant clarifying questions. Like one would do at the actual job exhibiting the characteristics the question purports to measure.
The car example is just stupid. Could you image how idiotic you’d sound beginning by asking is it a real car? You’re basically accusing your interlocutor of operating in bad faith (which they were).
Not just that, but the person said they did ask the interviewer what kind of car it was and what it was used for, at which point any reasonable person would explain it was a toy!
That interview question is basically, "We lied about an imaginary situation and were disappointed you failed to accuse us of lying mid-job interview."
> really, this is a stupid question and a waste of everyone’s time
Yeah, I think I agree. I was just responding to (what I saw as) sentiment that it was entirely unrelated to performance, which seems to overstate the case.
> Could you image how idiotic you’d sound beginning by asking is it a real car?
Tbh, "willing to sound like an idiot to double check assumptions" is probably something worth selecting for! I don't think that saves this question, though.
It’s been a long long time since I was interviewed for a job, but I have conducted a lot of interviews since then and any signal that the candidate has engaged with the question and has interesting thoughts about it is a huge plus.
FWIW I would never ask these kinds of gotcha questions. I just give simple programming problems and talk through solutions with the candidates, and then throw in complications to the questions to make them more interesting and test more areas of the candidates knowledge and problem solving abilities. Yknow, like what happens on the job every day.
Good for you, as you look for someone to work with, not someone to cut down their offer.
I am basically doing the same as I also interview people - but I also check the market from time to time as I am not company owner.
But I basically don't care about the offer if company pays guy much or not it is not my money and I only win if I get a smart, nice person who knows his job to work with.
It goes both ways - one interview turned into an acronym gotcha session. I quickly figured out that was not a place I would want to work; another friend that ended up working their later confirmed my suspicions.
I strongly agree with the sibling comment that this is a perfectly valid interview question.
One of the biggest red flags in an interview is if I ask a question and the person doesn't know how to say 'I don't know', because it suggests there's a big risk that if I assign them a task in their day-to-day work, they won't tell me if they feel unprepared to tackle it. That's a far bigger issue than not knowing that traceroute uses variable TTLs to figure out the timing along the route.
The problem with "I don't know" is that it's really not culturally appropiate to say! Americans are supposed to be rugged, resourceful individualists and asking for help is frowned on because it shows weakness. Can't do that in an interview!
I don’t doubt this happens but seems like a poor example. She effectively rooted out a bullshitter. No worries if you don’t know how a tool works, but just say I don’t know. That answer was nonsensical.
The purpose of an interview is not to root out a bullshitter but to find someone you can work with. If that guy doesn't know about TCP/IP, move on to the next topic. If the guy has poor attitude, be polite. Just don't waste time with making fun of the candidate, it does not reflect well on interviewer and company.
For what we know, the guy may well have been employing "test-taking strategies", and he may have been led down the garden path by the interviewer.
There's far too many posts in Rachel's blog where she goes on about "the one", who knows much better already, and here she channels the asshat that she complains about when she encounters him at work.
Each router checks its table for the destination, and if it doesn't know it, queries the next upstream router, its default route, the next hop. Each router likely ultimately informs you of the hand-off via a packet of some sort, and your then traceroute sends a ping/ICMP to each hop to learn how far away they are.
He maybe could've been pushed to expand on what he did know in more detail, but it seems like she just threw out SNMP as misleading bait, and he maybe mixed up ICMP and SNMP. She is right to call herself a troll, but wow, that's crazy to say she caught the guy in a lie of insanity.
The stepwise increasing TTL is the fundamental mechanism that makes traceroute work. Any answer that omits this is so vacuously incomplete that it might as well be considered wrong.
When you think about it, the candidate isn't even that wrong. Back then, at university, a certain professor would explain the oral exam to the candidate at the beginning. He would explain that he would incrementally increase the difficulty and skip from area to area. The goal would be to find the limits of the student's knowledge, the student would walk away feeling terrible, and he, the professor, didn't enjoy the experience.
That's how it ought to be, but here? OK, candidate doesn't know ICMP well, next topic, no need to waste time and dig in.
Here's another unfavourable thought: some people with abusive childhoods react very badly to dominance displays, and here is Rachel engaging in just that. One wonders what had happened before.
Downvoted for jumping from legitimate criticism of her interview methodology to very personal and completely baseless accusations. This is not the internet I want to live in.
Storytime! In a previous workplace a disagreement over fire safety with escalated into uncalled-for and unwelcome dominance behaviour from my supervisor. All attempts to deescalate were rebuffed, and now there is litigation from multiple plaintiffs, this person took out her sociopathic tendencies on many people. With a minimum of professional detachment or a HR department with a clue the peace would have been kept. (Yes, a few months later the fire marshal issued a code violation, as predicted.) You may not wish to live in that internet, but we live in a world where sociopaths are overrepresented in leadership positions.
Something rubs me here just the wrong way. Rachel complains about ageism and contempt for women in tech, and with good reason, and then she takes it out on an overenthusiastic candidate who can't read the room.
I wasn't denying the existence of antisocial people, I was decrying the public shaming of someone you've never met as a victim of child abuse, and now also as a sociopath, based on only a small thing they wrote on the internet.
I assure you, I've met many people who treat their interviewees worse who are not sociopaths.
Yea, they’re pointless. The amount of time someone spends on a truly difficult and important problem is maybe 0.1% of their job. And usually it’s better to just call in a domain expert anyway if it’s something that important. The other 99.9% - do they show up on time and work hard, do they care about the company, do they fit in with the rest of the team, etc, mostly can’t be determined in a short interview anyway.
