
Most common mistakes during interviews - aitorvs
https://aitorvs.github.io/post/most_common_mistakes_during_interviews/
======
wolco
"Who comes to an interview for a tech company not having done tons of leetcode
problems, studying algorithms and data structures to the limit?"

Most normal developers. Spending you time on leetcode means you want to get in
a faang. Most people are going for other roles.

~~~
azemetre
Eh IDK. Leetcode type questions are starting to slip into many industries and
types of companies. I recently interviewed at large finance (not trading
firms, retail banking/investment) and insurance companies. They both asked LC
medium/hard.

I was honestly taken a back. These companies aren’t known for “high” standards
and make up for the lack of interesting work with WLB (or at least it comes
across like that.

Just like how everyone copied google Qs a decade ago (how many toothpicks can
a tree yield...). I’m fully expecting everyone to copy FAANG like interviews
because someone in HR thinks it might signal better hires, and why wouldn’t
you want better hires right?

~~~
kamaal
So if they ask the same questions at Google and same at BigInsuranceCo, why
work for a lower salary at BigInsuranceCo.

If the interview is the same, you are better off working at some one who pays
better. As a side effect eventually there could across the board better pay.

~~~
azemetre
That's what I'm wondering myself. I've been taking more time to adequately
prepare for faang, because as you said why not work for the company that pays
more if the interview is nearly the same?

------
freddy418
This post reeks of elitist/holier-than-thou attitude that the whole industry
has unfortunately been feeding into. I also suspect that it is why there's so
little diversity in tech and why there's this absurd notion that there's not
enough "qualified" candidates to fill positions.

1) is something that I abhor because it allows the interviewer to assume very
little of the responsibility for communication, which is an exercise for both
people to come to a consensus of what the task is at hand. Instead of saying
"did I communicate this effectively", it's saying "it's the listener's fault
for not understanding me."

2) is very similar to 1) in that it also absolves the interviewer of any
responsibility for communicate. It's also an absurd proposition because it's
saying it is the interviewee's job to keep me, the interviewer, entertained.
This is absurd because the purpose of interviews is to vet a candidate, if
that's not the purpose, then the interviewer should make it more clear that an
hour's worth of a jester's time is being requested.

3) is specifying a criteria that might make sense for recent college graduates
or if the candidate knows what to prepare for. In my experience, no such
guidance is typically given, the most I've seen is "prepare for questions that
might be relevant to the role/job posting." The interviewer fails to consider
does he/she have a full time job? Did the interviewer actually provide
materials for he/she to study? If the questions the OP cited were not actually
provided, how do they know to prepare for those types of questions.

~~~
RandoHolmes
I think the point is that you can't control the interviewer, only yourself, so
concentrate on what you can control.

I think you're taking an overly unfair view of what the author meant.

~~~
freddy418
Then you're saying, "the system is broken, just live with it."

We know what's wrong with that statement in this climate.

~~~
RandoHolmes
So if I decide to change my own behavior rather than trying to change my
spouses behavior, it's because I'm really saying the marriage is broken?

That's a non-sequitur.

------
vansul
How useful are interviews in general? I've been led to believe that an
interview is a very poor indicator of future performance[0], and that an
interview biases the hiring decision in typically negative ways.

[0] [https://80000hours.org/podcast/episodes/will-macaskill-
moral...](https://80000hours.org/podcast/episodes/will-macaskill-moral-
philosophy/)

~~~
Kwantuum
I've recently started doing interviews for my company, and while there are
definitely candidates that we have been on the fence about accepting that
would probably have been a great fit, in the end, the false positive rate is
more important to us than the false negative rate. Maybe we missed out on some
great candidates but the criteria we used to evaluate them also allowed us to
avoid a lot of very bad candidates. The perfect interview process doesn't
exist, we have to make do with the fact that whatever the interview process
is, we will miss out on great candidates and end up making an offer to
candidates that will not work out. But indeed: for candidates, this means that
you shouldn't take rejections to heart too much: you might have been a great
fit for the role and a bad fit for the interview process. If you're
consistently getting rejected for positions for which you believe you are
qualified, maybe you need to get better at interviews, or maybe you're not as
qualified as you may think.

~~~
ende
> If you're consistently getting rejected for positions for which you believe
> you are qualified, maybe you need to get better at interviews, or maybe
> you're not as qualified as you may think.

This comment represents everything that is wrong with your technical interview
process. Big yikes.

~~~
RandoHolmes
agreed.

The lack of self-awareness displayed by that comment is kind of impressive.
Especially the bit about being so keen on identifying "bad" candidates, not
realizing that the entire point is that interviewers are actively bad at
determining good vs bad candidates.

------
ThePadawan
Really nothing I haven't read before. Apparently these are all mistakes a
_candidate_ can make.

I would appreciate it if companies finally acknowledged that interviewing is a
two-way street.

I have cancelled way more interviews due to red flags happily waved by
companies than companies have rejected me because I failed one of the 8
algorithms questions.

~~~
aitorvs
I agree with that comment. I have a part 2 of the blog post where I address
the issues I have seen in interviewers

[https://aitorvs.github.io/post/most_common_interviewer_mista...](https://aitorvs.github.io/post/most_common_interviewer_mistakes/)

~~~
ThePadawan
This adequately represents the 1:1 experience of one technical interview.

Let me cherry-pick an example: You mention that you don't read a candidate's
CV before your one interaction with them (the technical interview). As you
say, this is a debatable choice (I find it somewhat acceptable).

At that point, has anyone else at your company read the candidate's CV and
cover letter? Sounds stupid, but you would not believe how many people ask
about specific topics ("So have you worked with a relational database
before?") not in order to ask deeper questions about knowledge or experience,
but just in order to tick off checkboxes on their HR form. (This is not made
up, this has actually happened to me.)

This bigger issue of a company never asking themselves "How do we as a company
show that we actually give a shit about each candidate, and are not just
looking for a butt in an office chair" is where in my experience, _lots_ of
companies are still completely failing at self-reflection.

~~~
Izkata
> At that point, has anyone else at your company read the candidate's CV and
> cover letter? Sounds stupid, but you would not believe how many people ask
> about specific topics ("So have you worked with a relational database
> before?")

My understanding is that this situation happens as a test to see that you were
the one that wrote your resume.

~~~
ThePadawan
Huh, I didn't think this would be common enough for companies to start testing
against.

Thanks for the insight!

~~~
Izkata
It's not just a tech-worker thing, I remember being warned about knowing
exactly what's on your resume in highschool ~15 years ago.

------
diN0bot
> #2 - Not keeping your interviewer engaged > It is extremely simple, just
> think out loud

Yes, "think out loud" is better than being completely silent, but given that
many hiring decisions are based on how the interaction feels, including the
quality of the communication _in order to assess thinking skills_, candidates
can see huge returns by learning specific communication techniques.

I make videos on this topic (technical and non-technical interview and
negotiation skills), and happened to have just made a video on what to say
while writing code:

[https://www.youtube.com/watch?v=sv42PpY-
nK8](https://www.youtube.com/watch?v=sv42PpY-nK8)

~~~
roflc0ptic
Noting that I had a really intense negative emotional reaction to this video.
It's possible that I'm just not your target audience, and certainly the depth
of response felt... disproportionate, but I thought I might share my reaction
in case it was useful to you.

I think there was a combination of things that straight away disposed me
negatively towards it - the negative title (stop X!), the negative
introduction (stop x, again) and also the camera being so close to your face.
It had the effect of feeling like I was being simultaneously negged and
mansplained to by some overly aggressive dude (no doubt more an artifact of my
own life experiences more than the video. Stop telling me what to do, Dad.).
It felt very you-tube, but like, the uglier parts. I stopped watching pretty
quickly.

Glancing at your profile, it seems like you have a number of videos titled
"Stop X". I'm noting here that you describe this video as "a video on what to
say while writing code." There's a clear value prop there: What to say when
writing code! But it doesn't exactly come through in the first exposure to the
video. I'd watch a video on "what to say while writing code" because I have my
own opinions on it, and am interested in comparing my mental model with
someone else who's spent time thinking about good communication in a coding
context. Feeling scolded by said video made it a solid pass.

I think I read something purporting to be research about how closeup pictures
on faces tend to elicit stronger emotional reactions.

I did like that you were modeling perspective taking - "your interviewer is a
programmer who can read your code." Building a capable theory of mind is long
term work, and it's work that people who are drawn to computers often don't
do.

Anyways, thanks for sharing it, and taking the time to make those videos. It
seems like a worthy project.

------
tester756
Preparing for interview?

I tend to avoid it except things that are "obvious" but I tend to forget, like
you know - there's SOLID and everybody understands it differently and applies
it differently, I never remember the theory behind it.

I believe going without preparation means that you're "pure" \- you're talking
only about stuff you know or understand, not just seen 10h ago on some blog.

When it comes to questions I really love open questions like design something
or try find security issue

~~~
atoav
I think the most valuable preparation you can do is asking yourself long and
hard what the other side is looking for, and what you bring that they might be
looking for.

This is valuable for yourself as well, because you can avoid places where the
role they have in mind for you doesn't fit your expectations

------
angarg12
I agree with this, and I want to add to #3.

When you prepare for the behavioural questions, give answers of real
situations that you are very familiar with, and avoid "keyword soups". I've
seen quite a few candidates failing interviews because they gave almost canned
answers that seem to hit all the right points, but once you dig deeper they
aren't able to elaborate more.

------
sg47
Most tech interviews especially for engineers are a one-sided power dynamic
that does nothing except make the candidate nervous and eventually rejects
them arbitrarily. The ones that do get a job seem to think that that's the
only way to interview people and this cycle continues. What happens is this
becomes a boys club that excludes anyone else.

~~~
gnusty_gnurc
This is more apparent for people with anxiety too. My mind shuts down during
whiteboarding, yet people generally seem to think I'm smart outside any of
those scenarios.

I've already been employed for several years at different places, doing a
whole range of things, and it's weird that I have to practice some arbitrary
exercises in order to demonstrate to a company that I can work. This has led
to me landing at companies that don't require the bizarre jumping-through-
hoops that filters for the desperate and "committed".

And so far, I've not only yet to see interview-style programming on the job,
I've seen utterly atrocious practices.

~~~
pavas
I work for a FAANG company. The interviews were quite stressful, and my goal
for every question was to push through and at the very least make some
progress instead of giving up.

I don't make use of any of the algorithmic skills I was interviewed on, but I
do have to push through stressful situations regularly and make progress in a
timely fashion. I do think that if I weren't able to do that during an
interview situation, I wouldn't have been able to do that on the job.

Maybe I wouldn't have any stress in my current position if I were 10x smarter
or 10x more experienced/knowledgable, but that would also indicate that I were
underleveled.

I'm certain there are many smart and skilled individuals that wouldn't be able
to consistently make it past a tech interview loop unless they put in lots of
"unnecessary" extra work.

~~~
bogwog
> I do have to push through stressful situations regularly and make progress
> in a timely fashion.

You mean like everyone else in (almost) every single job ever? Do you think
developers at inferior companies just sit around blissfully typing away with
half of their brains shut off?

Those interview processes say practically nothing about candidate’s
fit/performance for the job. This has been shown to be true many times. The
awkward hoops put in place just result in the interviewer having ample
convenient opportunities to turn down a candidate for any reason. Like maybe
in the back of their mind, deep deep down inside, they actually _don’t_ want
to hire that black person who just wasted weeks or months of their life
grinding useless leetcode questions.

~~~
pavas
There's stress everywhere, agreed. In my experience, holding all else equal
the amount of stress you have is correlated with the cost of screwing
something up or of not delivering on time. Holding all else equal, that is
also correlated with compensation, and if stress is too high relative to
compensation that either means you're getting a bad deal or you're in over
your head.

> Like maybe in the back of their mind, deep deep down inside, they actually
> don’t want to hire that black person who just wasted weeks or months of
> their life grinding useless leetcode questions.

That's a reason to push for standardized interviews with objective questions,
so you decrease the effect of interviewer bias and focus on candidate
performance.

There's definitely something to be said here though about increasing the
knowledge of how to get into top tech companies for disadvantaged groups,
because I don't think it's common knowledge.

------
smcg
In my experience this article applies very well to competent small and medium
sized companies. My experience with large companies with names like Floogle or
Gloomburg is that the interviewer is just blindly looking for you to read
their mind and is irritated with any clarifying questions.

------
yowlingcat
Ah, this topic always seems to stir the pot around here. I think these are
decent call-outs from the point of the interviewer, so I'll add a couple of my
own from the point of a candidate:

1) not screening the company during the interview 2) not preparing by doing
"warm-up" interviews for roles you won't be too sad about if you don't get 3)
not doing enough interviews to get multiple offers for negotiating leverage

For my first point, you'll learn a lot about the company and how they work
from the interview process. If the company has dysfunctional elements to its
corporate culture, depending on the size, it's quite likely they'll be
surfaced here. Not only is this one of the first impressions of you for them,
but it's one of the first impressions of them for you. Pay attention to what
your gut and intuition tell you here. Every time I've broken this rule, it's
bitten me.

For my second point, I think that people often forget that the only way to get
better at interviewing is to just do it over and over again. It's a little
hard to do that in a synthetic environment because it's hard to trick your
brain into behaving as if it is real unless it actually is. But wait, you may
say, treating an interview like practice is unethical! But I'd disagree. After
all, if you really do well on the interview but you're not chomping at the bit
to join, they might be more willing to negotiate and make you an offer that
would make you reconsider. But, you likely know (and can force-rank) the roles
you'd be most willing and least willing to take if you had the opportunity, so
make sure to go through the sequence from least desirable to most desirable so
that you have more leverage.

My third point is probably the most crucial. You need the BATNA (best
alternative to negotatiated agreement) of accepting something else or staying
where you are to be able to negotiate. Otherwise, you have much less leverage.
This is part of why timing and interviewing for less desirable roles is
preferable, because you are more likely to negotiate with an offer for your
more desirable role by the time you get there.

~~~
wtracy
> screening the company during the interview

Can you offer any advice or resources on what to ask or watch out for in this
area?

~~~
yowlingcat
That's hard to say. It feels a lot like dating. First of all, you want to
avoid lemons. Secondly, you want to avoid glaring mismatches, so things can at
least work out and be sustainable. But there sure are a lot of places where
mismatches can occur!

Beyond company fit, there needs to be team fit (and proximally manager fit)
and role fit. A lot of this depends on size, too. Company fit is going to be
really important if you're anywhere early. But beyond a size, it matters a
whole lot less than manager+team.

For the latter, you have to work with the team and manager on something to get
a sense of what their style is and whether you'll clash. Try and find some way
to talk about a problem as if it's a real world scenario, and see how easy it
is to intellectually collaborate towards a solution. Does it feel natural or
no? Would you trust this person enough to work with them for 8H+ a day? Keep
this in mind as you compare offers.

But it's hard. You can only discern so much, and this stuff is really easy to
fake in an interview. You see different shades of people once you really have
to rely on them in the dint of production. This is part of what makes warm
intros so powerful -- if you've worked with someone you trust and respect
before, and they've worked with someone they trust and respect before, it's
more likely that you and that other person will transitively be compatible.
Move too far outside that transitivity and you're taking existential risks.
This is why it's not always a bad thing to move around a bit more in your
earlier career -- it can open up your second degree circles a bit more once
you hit mid career.

------
rsecora
Another of the most common errors is to lie or to exaggerate in a side work
experience. If it's catch, it will jeopardize the interview.

A common example is to fill the CV with buzzwords and when asked about them,
the knowledge varies from shallow to non existent.

~~~
EForEndeavour
Résumé: "Achieved state-of-the-art classification accuracy on MNIST dataset by
implementing a residual attention convolutional neural network with Keras and
TensorFlow on Google Cloud Platform"

Reality: shift-entered my way through an interactive tutorial in Google
Colab's free tier like I was button-mashing a videogame combo

------
alexanderdou
> Not keeping your interviewer engaged

Ugh. I'm going through the interview process right now and this peeves me so
much

The presumption that I, the supplicant, need to be interesting and keep the
interviewer, who has deigned to give me 30 minutes of their time (often 23
minutes because, "sorry I'm late but I also have a hard stop at the top of the
hour") "engaged" makes the interview so lopsided, awkward, and just
nonproductive

That being said: > Not preparing for the interview

Is completely legit. I have walked out of a couple of interviews wishing I had
prepped a little bit more so that I could make the conversation a productive
one

------
RivieraKid
Regarding 2, I would simply solve it, and then maybe ask about using the same
number twice to fine-tune the solution.

In real-world problems I almost always think of corner-cases. So I think that
the interview process is flawed - at least in my case - by assuming that not
asking about specifics generalizes.

In general, if the interview process is designed in a way that reading a
random article like this on HN helps you pass it, I'm kind of skeptical how
well it's measuring future job performance.

------
ipnon
Are algorithm interviews just a legal loophole? They allow companies to do
something that is nominally illegal: discriminate against candidates with
anxiety disorders and women.[1]

[1] [https://news.ncsu.edu/2020/07/tech-job-interviews-
anxiety/](https://news.ncsu.edu/2020/07/tech-job-interviews-anxiety/)

~~~
RandoHolmes
It's not possible to avoid "discrimination" against people with anxiety
disorders, it's the nature of their disorder.

It's a bit like saying the NBA shouldn't discriminate against short people. At
the end of the day, the best performers tend to not be short, that's just
reality.

In the same way that anxious people tend to struggle in an interview.
Obviously you shouldn't be going out of your way to discriminate, but the
reality is what it is.

~~~
pseudalopex
The study suggests how to control for performance anxiety in interviews. Why
do you believe it's not possible?

NBA scouts evaluate how players perform in real games. Most tech interviews
are nothing like the job.

Many countries require employers to reasonably accommodate people with
disabilities. Not going out of your way to discriminate isn't enough.

------
MarkMc
'Ask clarifying questions' and 'think out loud' are also two of the
suggestions in this excellent video from Google showing an example of a great
technical interview:
[https://youtu.be/XKu_SEDAykw](https://youtu.be/XKu_SEDAykw)

------
yankjenets
> can I multiply a number by itself

This is a great clarifying question. Ambiguous from the prompt.

> what shall I return if there are multiple numbers meeting the criteria

This is a decent clarifying question. I think it is better expressed as a
clarifying point instead of question--mention to the interviewer your thinking
out loud; something like "if there are multiple options, I'll return an
arbitrary pair". Ask if they are okay with that.

> is the list sorted

If I were the interviewer, this question would almost make me dock points off
of the interviewee. Maybe not that strong as I do try and ensure people are as
comfortable and open as possible in asking clarifying questions, but this
barely qualifies as a clarifying question in my opinion. It is almost
irrelevant to the prompt; if the lists were sorted and the interviewer failed
to mention / there was some "trick" that they expected you to clarify, that
would be an awful interview question.

That being said, overall agree with the sentiment and yes you should try and
always ask clarifying questions and ensure you understand the problem
statement.

~~~
tomsmeding
Asking if the list is sorted was also the very first question that popped up
in my head, because it makes the difference between a linear and a quadratic
algorithm. Contrary to, for example, having the choice between an n log n
algorithm and a linear algorithm, when given the choice between a _quadratic_
and a linear algorithm, it is very rare that the right choice is the quadratic
algorithm. (Semi-related: [1])

(EDIT: after thinking about this more than two seconds, the quadratic
algorithm for unsorted input can become n log n by sorting the list, though
that takes linear space. This would certainly be a clarifying question.)

The other questions would be less obvious to me, though I'd encounter them
while thinking more than 2 seconds about the problem, I suppose.

Or maybe this just outs me as an ex-amateur competitive programmer :)

[1]:
[https://accidentallyquadratic.tumblr.com/](https://accidentallyquadratic.tumblr.com/)

~~~
yankjenets
And if you had a magical oracle that spat out the two numbers if a solution
exists, and otherwise told you no solution exists, you would have an O(1)
solution.

Just because you can ask a question whose answer makes a drastic difference
between the best algorithm involved, doesn't mean it is a good question.

(and note I said "_almost_ make me dock points...". And if the answer to the
question was "yes, the list is sorted", I would _certainly_ dock points off of
the interviewer/company if I were the interviewee for not giving that
context).

------
fenesiistvan
I like that there are no 10 points and boring conclusions chapter

------
andersco
Great list. Adding one of the most common mistakes I see during interviews:

Not saying “I don’t know” when you clearly don’t know the answer to a
question.

------
29athrowaway
I would say: budget your time.

Try to ask: how many exercises do you have to solve, and how many parts does
the current exercise have.

------
throwaway_pdp09
Prior to getting an interview you read the job ad. They want original, problem
solvers, dynamic, goal-oriented etc. etc.

I've always wondered why they don't somehow all me to demonstrate this before
it gets to an interview. Let the candidates winnow themselves out. It could be
so easy, it should work, but they don't. IDK, perhaps it works only in theory.

