That time when I failed the Microsoft interview

In the end it came down to either pressuring the client to embark on a complex cloud transition in time for a major sports event (that was a make or break event for the customer) or, as my friend recommended, start with a PoC but do the risky transition after the sporting event to minimize the potential for a catastrophic failure if things didn’t go to plan.

He didn’t get the job because even though the technical attributes were all good, he should have pressured the customer.

My takeaway was that interviews are a game with their own rules, and you have to play by those rules - demonstrating some sense of judgement outside the parameters of the game will not be tolerated.

Possible reasons.. Sometimes a team is growing so fast / or turnover is so high / everyone is so busy / etc that they cannot really stand up a proper interview process .. and/or they just need to get people into seats, and are happy to fire fast later.

Sometimes a job is so boring and team leads have so much time on their hands that they can construct immaculate interview processes and spend hours grilling candidates.

Of course I told the interviewer I'd heard it before and then gave the correct answer. In my case we just ended up chatting about previous experience instead of doing another brainteaser and I ultimately passed the interview, I think. But afterward the recruiter strung me along for weeks telling me they wanted to make an offer but not giving me one, and I ended up going to Microsoft instead.

Not the worst interview experience I've had, though. That would be the time I interviewed for a full time position after an internship and a group of guys who knew me and had worked with me all summer asked me a pointless brainteaser as the only interview question. I crashed and burned for a full 40 minutes in front of them. Humiliating, and pretty much a pointless hazing ritual as they offered me the job anyway. Luckily I got a better offer and was able to turn them down.

Here are some other brainteasers I've been asked in interviews. I actually think these physics based ones are fun (probably because I had no trouble solving them), but they're still terrible interview questions:

You're in a boat on a lake with a bowling ball. After you drop the ball overboard and it sinks to the bottom, is the lake water level higher or lower or the same?

Three balls are on three downward sloping tracks. One track is a straight line down to the end, the second is the same except for a small hill in the middle, and the third is the same except instead of a hill it has a small dip. All tracks start at the same height and end at the same height and cover the same horizontal distance. The balls are released at the same time and roll to the end without leaving their tracks. Which one gets there first?

The coding questions that require an "aha!" moment are very similar to brain teasers, and should also be avoided.

When I conducted interviews for FAANG, I asked somewhat simpler coding questions, something around DFS and/or topological sorting (without calling it by name, of course), because those are thing which you might actually need to implement at work: people sometimes traverse JSONs, and people sometimes resolve dependencies. No one has ever told me "oh, I know this problem, it's DFS", because surely I know they know it. Just show me that you can write the code.

I also got this riddle, in 2015. I couldn't solve it. Tbh, I think it's a terrible question. There isn't really a step-by-step problem solving process, but you just need to have a "leap" to realize you can weight the marbles in groups of 3. I also got rejected. It's crazy to get rejected from a one-question riddle like this

On the other hand, if I heard that a candidate had not mentioned they had the same question twice, or later let it be known they already knew the answer, I would lose a lot of trust in them.

Be honest; it’s more likely you will be hired by honest people.

They received a crash course in the power of Haskell ADT and `deriving (Show, Read)`.

(1) the riddles you already know you answer after some staged deliberation to pretend you are working it out from first principles using your genius brain (bonus points if you can work "first principles" into the conversation).

(2) The riddles you don't know the answer to are the ones you say you already read in a book or online and repeat this until you get back to a (1)

In this case, the goal is to hire great engineers; and great engineers do not memorize solutions to every problem, nor can they come up intuitively with great solutions in a matter of minutes.

Then they broke me. I tried to give feedback on the products, interviewed, and really tried to reach out to them. Mostly ignored (except Outlook team, thanks ). The heavy marketing and tech debt within Windows is what did it for me. Rant over.... the interview felt like some trick questions at that time.

Heh, Microsoft might actually have been weird to target in 2015, especially in SV / startup circles, given that pg had declared it dead in 2007 (https://paulgraham.com/microsoft.html) I guess the Netherlands didn't get that particular memo.

In 2026 Microsoft might actually be interesting again, given it's up there in the Mag 7 jockeying for position in the AI race. I know it's gonna be impossible to get an accurate vibe-check on HN, but I wonder what younger folks think of it today...

Interview questions like this are useless as they are not an accurate approximation of a real work scenario. I've frozen up at a whiteboard in an interview before, and then figured it out on the drive home.

The best approach I've found is to do a send home quiz, and then ask them questions about the quiz to test understanding. The test also shows coding habits, which tells you a lot right there.

Bonus: put some typos in the quiz that don't matter. Red flag for the people that get hung up on that.

How do you guys view external contractors(the one with email address start with v-xxx)

I was contractor for MS for a while and it was not a very positive experience. i was kind of being forgotten and only be mentioned when convenient. I went by months without any actual real work done.

So the question was something like, here is a table of predicted probabilities for credit card transactions (hypothetical table, I do not remember the exact quantities), but it looked something like this:

    Amount, Probability, ActualFraud
       $5 ,    0.2     ,  0
     $100 ,    0.5     ,  0
       $3 ,    0.7     ,  1
       $1 ,    0.9     ,  1

My response was that a proper decision model should take the dollar amount of the transaction into consideration, so the decision should more like be `$*p > threshold`, where this threshold meets your precision and recall for preventing dollars lost instead of the binary yes/no.

The interviewers English was not great, so after all that I was just like "well to answer your exact question, it could be anywhere between `0.5 < p <= 0.7`"

Did not make the second round!

Sometimes he asked the same question again and when someone remembered the answer, he still went "gotcha!" only with a changed answer.

The lesson I learned from that guy, was that sometimes a question says more about the person asking it than about the person answering it — more precisely that men with small egos bend reality to get the outcome they prefer.

The appropriate strategy with him was to ask in a Socratic way while stroking his ego: "But haven't you thought us X is Y? I would like to get it correct!", then he would squirm around and admit that yes, this is also correct.

This type of dynamic can also occur in interviews.

And now after decades of research, we're still using magic potions that mostly don't make sense.

Chief among those thoughts is that we can't design a clearinghouse for a banking system that already has 11 components and the request is just two simple sentences asking for a design. I apparently have an hour to complete this design task. An hour is so laughably small a time to get onto the design phase.

Again, I understand what they are going (I'm just not practicing it) for but it all feels like they're hiring for tennis but interviewing for ping pong.

I've never interviewed there, or been asked that question, but I think it would be a lot of fun to answer.

The question wasn't "do you know this riddle", she just wanted the riddle answered. No need to make it more complicated.

There's no lie in withholding information never asked for. It's possible the request for a new riddle was interpreted as a ploy to get an easier riddle.

Same with leetcode at startups. It makes no sense. You’re almost certainly not going to do algorithms work. It’s only relevant if you’re looking for people willing to grind bullshit, which is certainly some jobs, but, again, you’re almost never doing this under arbitrary time pressure with someone watching over your shoulder judging and not helping.

My advice: if you encounter this, don’t work there. If a company doesn’t value testing relevant skills for candidates, don’t expect leadership to be strong critical thinkers once you get there.

In an industry that loves calling itself "engineering", it seems nothing further of value can be established?

I wouldn’t go that far, but I think it’s perfectly fine to reverse-engineer the interview game and reap the rewards. There’s no reason to feel guilty about it.

At the end of the interview other interviewer asked from the distracted guy if he has any questions and he came up with the stupidest brain teaser question ever, I don't even remember what it was, but after I answered it, he changed it again and then I asked the answer from him, and was very arrogantly said "I'm sure you know the answer" and I immediately said back, "But I guess you really don't know the answer to your own question right?". He was dumbfounded. I think he didn't expect me, the candidate to call him out.

Afterwards, I immediately sent and email to the recruiter about how bad the interview was and one interviewer was being more than 30 mins late and withdrew from the process and added Deutsche bank to my black list.

Now there I've made it much worse (or better!) than the actual reality, which is that there's just not enough quality engineering jobs no matter which way you cut it and all of this theatrics result from scarcity.

Source: as an interviewer, I had to sit in that meeting.

1. Suppose you have a binary tree (NOT a binary search tree) where each node with pointers to its parent and children. Given pointers to two arbitrary nodes in the tree, find their lowest common ancestor.

2. My favorite: given a uniform random number generator mod 5, create a uniform random number generator mod 7

3. Forgot the exact question, but something along the lines of: suppose you want to keep track of function arguments as you call them. How do you do that?

I got (1) and (2) and utterly failed (3). (3) is entirely trivial and basically a stated fact if you know how anything about how operating systems work, but I was a freshman in college and didn't know that function arguments got pushed on a stack in memory, so I was totally lost.

The rejection was so generic and there's so much random bs that goes on it could be anything that lead to that result.

I remember speeding through the loop for something closely analogous to my job at the time, only to be suddenly told by the hiring manager (who up to that time was a strong supporter) in a final interview that I wasn’t qualified. Not wanting to invest any more energy, I formally withdrew, only to get a call from him protesting why I’d do such a thing. Or being told to leave at the end of the day only to be called to drive back 20 miles immediately during dinner, and finding out later that was a mistake. Or being literally screamed at (spittle in my face!) that HPC was only MPI and nothing but MPI. Or being yelled at that Windows Server was exactly the same as an enterprise storage system like EMC/HP/Hitachi. The hits go on.