How to stand out in a McKinsey interview?
Your success in a McKinsey case interview is not defined by you solving the case. The interviewer sitting across the table from you is not trying to assess if you found the right case answer. Instead, they are trying to determine whether you have the necessary skills to be a good consultant.
Hence, once you mastered the required skills, it is important that you learn how to convey them in the interview. In other words, you need to make it easy for the interviewer to see your skills at their best within the 20 minutes allocated to the case interview.
We have put together a few tips followed by interview examples of how you can truly stand out in a McKinsey case interview and make it as easy as possible for the interviewer to see that you will make a great consultant:
1. Make your thought process as transparent as possible
2. Always sanity check your answers
3. Explain why you chose that structure
4. Treat the case as a real-time project, not a theoretical exercise
Let us look at each of them in detail and illustrate them with examples from real McKinsey interviews.
Tip 1. Make your thought process as transparent as possible.
Mistakes are made in almost every single McKinsey case interview. It can be a stressful situation and it is very easy to slip during a step of a calculation or forget a critical fact that was mentioned somewhere during the case once it is time to give a recommendation. Whether that is a problem or not almost always comes down to the transparency of your thought process.
If the interviewer has a good understanding of where you made a mistake in what was otherwise sound logic, an error will easily be excused. If you come up with the wrong answer, and it is not clear where you made it and why you will be much less likely to pass the interview. At the same time, if you arrived at the right answer, but did not clearly communicate your thinking process and reasoning, just the fact of solving a case will not mean much.
Example 1 from a case interview.
Context
The candidate is given a bunch of charts that contain bits and pieces of information. Using these charts, the candidate needs to assess the market size for the client’s product in three different regions.
What most candidates do
In most case interviews, the candidate immediately jumps into executing the task. Head down, they are vigorously crunching the numbers. They are speaking through the math, “I take X%, multiply by Y, then divide by N” and you can see that they are trying to lead the interviewer through the thinking process.
This is not the transparency of thought that the interviewer wants to see. Transparency is not that much about communicating your immediate action (arithmetic or not), it is about communicating how you plan to approach answering the question and why.
How to stand out in McKinsey case interview
A great candidate takes a moment to investigate all the charts and think through the overall approach. Then, they outline their approach to the interviewer, without doing math just yet. They speak through the steps they are going to take and explain why they think that is the best approach. Often the approach has sound logic but is not 100% correct. The interviewer asks a couple of follow-up questions, and they fix the approach together.
Now the candidate can start doing the math. They might make an arithmetic mistake and not arrive at the right answer but that would be ok because the interviewer knows that their logic was good and they are aligned, which also means that no precious time is wasted. In many cases, once the logic is discussed the candidate will get exempted from doing the math or they would need to run numbers only partially.
Example 2 from a case interview
Context
The candidate needs to value a company. They are given a few numbers, but not told anything about how to value the company. The candidate seems to be unsure as they have never valued a company before.
What most candidates do
Most candidates who don’t know how to value a company struggle over the numbers for a few minutes, trying to put them together in a random manner. Typically, they give up in a few minutes or come up with the wrong answer. They are not trying to talk about their thinking process and involve the interviewer, likely because they are too concerned to appear wrong.
How to stand out in McKinsey case interview
The fact that you don’t know how to value companies is not a problem. In fact, you are not expected to. What matters is that you try to figure it out with the help of the interviewer.
For example, a great candidate might say “I’ve never valued the company before, but here is what I think. The company value in this context must be dependent on how much profit the company makes, is that correct? Ok, this is how I would assess the profit. Now what I am not sure about is the valuation multiple that you gave me. Could you help me understand how it is used when valuing companies?”.
The candidate is clearly communicating their thinking that is based on sound logic (of course company value has something to do with profit), moreover, they involve her interviewer to problem-solve together as typically happens in a real McKinsey project.
As you can see, you don’t need to have experience in valuing the companies to be a great candidate. What you need is transparency and articulation of your problem-solving approach.
Example 3 from a case interview
Context
The candidate needs to value a company. They are given a few numbers, but not told anything about how to value the company. This time candidate obviously has a lot of experience in valuing companies.
What most candidates do
Most candidates who know how to value companies from previous experience, with visible excitement jump into the math. In about a minute they reappear with a broad smile and the answer “The company value will be 5bn dollars!”. The answer is correct, but they didn’t explain how they got there, what the chosen approach and why.
Maybe the answer just randomly happened to be right. Sometimes, the interviewer might take time to go back to the beginning to understand the thinking. Sometimes, that will be it and the candidate will fail.
How to stand out in a McKinsey case interview
A great candidate would start by asking a question. “Look there are a couple of approaches that we can use here. I suggest that we use approach A because of these reasons. What do you think?”. Once the approach is aligned, the candidate proceeds to the math. They made their thinking transparent.
Example 4 from a case interview
Context
The candidate has a few charts and needs to answer the question “what does this information mean for our client?”
What most candidates do
Most candidates start randomly reading numbers they see on the chart. They are convinced that they need to be talking non-stop even though they haven’t yet formulated their thoughts and don’t know what exactly they are looking for. This candidate confuses transparency of thought with speaking mindlessly all the time.
How to stand out in a McKinsey case interview
A great candidate takes a minute to look through the charts, then communicates the summary of what they see in a form of the key insight followed by a hypothesis on the reasons why the insight is happening.
Tip 2. Always sanity check your answers.
As we mentioned above, you will almost never be punished in a case interview for getting a calculation wrong. Getting it wrong without realizing it, that’s a different story. In order to stand out in a McKinsey interview, a candidate needs to be able to quickly assess if the answer makes sense in the given context and correct the mistake if it doesn’t.
Example 5 from a case interview
Context
The candidate calculates the future revenues of the client. From the background information, the candidate knows that the total market size for the client industry and geography is 20bn USD. As the candidate works through the math, she makes one of the most common mistakes driven by stress: getting a decimal point in the wrong place and arriving at the answer that is 10 times higher than it was supposed to be (in this case 50bn USD instead of 5bn USD).
What most candidates do
Most candidates when arriving at the answer 50bn says “Wow, it looks like a lot of money. I think our client should definitely go for this opportunity”. The candidate didn’t benchmark the result vs the rest of the information provided through the case and didn’t notice that the client revenue is larger than the whole market, which by default can’t be right.
How to stand out in a McKinsey case interview
Great candidates when arriving at the answer of 50bn quickly realize that there is a mistake and say, “That doesn’t make sense, let me see what I did wrong. Let me review my assumptions and my math”. It immediately shows that the candidate will make a good consultant.
In real life, your ability to catch errors when they are made is much more important than your ability to not make errors in the first place. It shows that you are comfortable with numbers and have good judgment, and that’s what the interviewer is looking for.
Tip 3. Explain why you chose that structure.
This tip is related to general thought transparency, but we are highlighting it separately as this is the part where we see problems happening very, very often. Almost every case can be solved in several different ways. Almost every problem can be structured differently. What is important is not to have the perfect structure, but to showcase why the structure was chosen, and the logic behind it.
Example 6 from a case interview
Context
The candidate is asked to outline the areas they would investigate when deciding if the client should enter the new market.
What most candidates do
Most candidates after disappearing into writing for a few minutes emerge with an answer “here are the four buckets I would look into” and then read the headings of those buckets and sub-bullet points.
There is no way for the interviewer to know why those buckets were chosen. Were they random? From some book? From previous experience? Or was there sound logic behind them? The interviewer will ask a lot of questions digging into the logic. The candidate then gets stressed, feels not in control, and starts thinking “something is wrong with my framework”. In fact, there might be nothing wrong, except the was no transparency of thinking.
How to stand out in a McKinsey case interview
A great candidate leads the interviewer through the issue tree, consistently splitting all the branches. The candidate is always MECE, but most importantly, they give a clear rationale as to why they chose that structure, how they are working through it, and the steps they are going to take through the case to get to an answer.
Tip 4. Treat the case as a real-time project, not a theoretical exercise.
When approaching the case, think about it as a consultant would think about a project instead of just a case that someone came up with to test your skill. Immersing yourself in the problem will not only help you avoid being too generic and theoretical but will also allow your interviewer to assess how it will feel to work with you.
What most candidates do
Use schoolbook lingo such as “let me build a framework”
Treat the interviewer as a teacher who will grade them
Do not demonstrate personality
Make generic statements (e.g. “I would look into competition”)
How to stand out in a McKinsey case interview
Immerse yourself in solving a problem with passion and genuine interest
Treat the interviewer as a teammate and engage the interviewer in problem-solving
Stay yourself, giving the interviewer a sense if it would be pleasant to work with you as a person
Be specific about what you look for (e.g. “I would look into competitors’ market shares and compare them with similar data from the market we most recently entered”)
