Hi,

I would recommend following a step-by-step approach to impress the interviewer without knowing their intention to ask this brainstorming question. Sometimes the interviewers want to evaluate your creativity, sometimes they would like to understand your judgement for most important drivers. Here is what I mean with step-by-step approach:

1. Ask for a short time (10 secs) and take quick notes about 6-8 ideas you can find in that topic. Even unrealistic ones make sense to be included in this long list
2. Choose the most relevant and critical 3-4 ideas, group them in your mind under sub-topics
3. At the end of 10 secs, explain the groups (sub-topics) and support them with 3-4 critical ideas
4. If interviewer would like to evaluate your creativity, they would ask for more ideas. Then, use the remaining ideas in the long list, deliver them using the same grouping (sub-topics) you have determined at the beginning
5. If the interviewer asks for more ideas, don’t panic. Try to find more ideas instantly, as you speak and don’t limit yourself. Try to be as creative as possible
6. If you are stuck and out of ideas, you can kindly say that that’s all you can find

Hope this is clear and it helps!

Hi there,

This is a great question.

The #1 way to help yourself with any problem is think "what is my objective"? I.e. what is my target variable? What does good look like?

I should prompt you for this, but I'll give you the answer. You want a good driver dispatched quickly. That's it.

So:

1. Radius needs to balance speed to passenger (i.e. the larger the radius, the longer the passenger has to wait) with quality of candidates.

Larger net = better candidates but worse wait. Smaller net = shorter wait but worse candidates.

2. This one's easy - customer rating and/or arrival/delivery speed

In terms of #1, you need to understand the independent distribution of driver quality in the specific location in which you sit then set constraints around the minimum level quality driver you're willing to accept based on customer research of satisfaction thresholds.

^Of course, in denser locations the radius will be smaller and in less populated areas, the radius will be larger.

Pre-structure questions

1) Clarify the business model. Even if you think you understand it, try to repeat it to make sure that you understand in correctly.

2) Clarify the objective. Here make sure that your goal is:

• Measurable
• Has a time-framed
• Has / has no limitations

e.g. Should I invest 100k in this business for 1 year if I want to get 15% return?

3) Ask the questions that will help you build a relevant structure and remove ambiguity.

e.g. if the case is about oil&gas company which revenues are decling, ask if it is Up / mid / down-stream problem. In this case defining a revenue stream is critical to seting up the right structure.

Post-structure questions:

It's kind of hard to generalize all the cases. I will try to provide a general algorythm here:

1. Ask for a piece of data / info you've defined in a structure
2. Compare the data with historical trend / becnhmarks
3. If you find something interesting ask for the root / cause or state the hypothesis
4. If no root/cause at this point available - ask for segmentation to drill down further
5. Once you are done with analysis in one branch of your framework (found the root-cause / found nothing interesting) - summarize what you've learnt so far and move to the next one

Again, the last one is super high-level and the devil is in details:)

Hi,

Great question. Strong brainstorming approach is something that can add a lot to your performance and separate you from other candidates.

There are typically 3 stages of any brainstorming exercise at MBB:

1) Prepare a long list of potential solutions to a problem

You need to create a MECE list of relevant ideas, which can solve the problem. Ways to approach:

• Zero drafting - this technique helps establish what you currently know and get your initial ideas out of your brain and onto paper
• SCAMPER technique
• Substitute - take a part of the product, service or process etc. that you could replace with another to see whether it will result in improvements, such as efficiency gains
• Combine - one idea might not work alone, but you could combine several ideas, processes or products into one more efficient output. A great example for a combination of two different products are cell phones with an integrated camera
• Adapt - an idea that worked to solve one problem could also be used to solve a different problem. An example for the successful adaption to a new situation is Netflix. The company started out in 1999 as a DVD rent provider, but they quickly realized that the future belongs to online streaming and changed their product
• Modify - Changing part or all of the product or process, or distorting it in an unusual way
• Put to another use - put the current product or process in another purpose or use the existing product to solve problems. For example, this technique can be used to learn how to shift an existing product to another market segment or user type
• Eliminate - eliminate inefficient processes with the goal of streamlining them. An example for eliminating is Apple’s approach to not include an optical CD drive in their laptop to make them thinner and lighter
• Reverse - explore the innovative potential when changing the order of the process in the production line
• Analogy thinking - explore inspiring cases and mix their top features with your industry, to come up with new powerful concepts
• Forced connections - take two unrelated concepts and forge a relationship between them

2) Prepare a shortlist of solutions

You need to select solutions that would be financially adequate, could be achieved in the foreseeable future and do not face any constraints of the client situation.

3) Prioritize solutions

Apply 80/20 rule to select 20% of initiatives that would generate 80% of the upside effect.

Best,

Anton

Hi,

Always take:

• 1-2 min for initial structure. But the faster the better. 1.5 looks fine
• 30 sec to analyze the graph / table. Very often you can come up with more than one conclusion from the graph / table(e.g. main conclusion, outliers, correlations)
• 30 sec - 1 min for questions on creativity. It's really hard to be creative "On-the-go". Spend this time creating the buckets of ideas and then the ideas within the buckets.
• Up to 1 minute for the conclusion. Again, the faster the better. But always take the time! Your conclusion should be very well structured and your arguments should include supporting numbers and you need time to collect them. Spend 1 minute on collecting the numbers for the arguments. Remember that 70% of your arguments should have numbers

It's a bit more tricky with taking time during the case:

• It's not OK to take 30 seconds and then come up with just 1 or 2 ideas. And then if the ideas are not correct to keep the science again. This is called "Guessing"
• It's OK to take 30 seconds, draw a new structure (or continuation of your previous structure) and come up with a structured way to approach the problem further.

Best,

Vlad

Hi Anonymous,

relevant questions at the end are a great way to show your interest in the company and get additional points. Ideally, your questions should respect the following criteria:

• Should not be related to something you could easily find online
• Should not be related to the firm per se (eg how is XYZ in Bain), but to the experience of the consultant (How did you find XYZ in your experience as a consultant? Which challenges did it bring to you?). Ideally, you want the interviewer to feel important and/or share a positive experience. This is the easiest way to leave a final positive impression.
• Should help you to understand better the core values of the company; this will help you to understand if that company is a good fit for you and evaluate your options in case you have multiple offers.

In the first reply in the following thread, you can find some more information and some examples of questions:

https://www.preplounge.com/en/consulting-forum/open-house-at-bcg-311

Best,

Francesco

Hi Anonymous,

if you understand you forgot to clarify a point when presenting the structure, I would recommend to ask the question at that stage, ideally connecting with some parts of the structure itself, in order to make less evident you forgot the point before (communication is always key in a case and part of your assessment as well).

Assuming the structure presented is the one you described and you just completed its presentation, the following would be a possible way to formulate the question:

“(…). Now, we can start with the first point related to the possible markets to select. In order to understand that, I think it would be useful to know in which markets the company is currently active. Do we have information on that?”

Best,

Francesco

Hi Anonymous!

You touch on an important point here. Many candidates don't understand what distinguishes the clarifying questions at the start from later analysis-related questions (asking for market data. financials, etc.) In general, asking such analysis-related questions at the start is bad! It comes across completely arbitrary, and the interviewer will ask himself why you are asking analysis-questions before even having layed out an analysis approach (the structure)! It just makes no sense to ask for data before laying out your structure, because this information will have ZERO impact on this structure (--> the logic according to which you should address the question).

The clarifying questions you ask at the beginning have the following objectives:

1. Completely understanding the context/situation (including, unclear terminology, but also, for example, the business model of the client if unclear!)
2. Understanding/narrowing down the actual question(s) of the client (very often the question is poorly/vaguely stated in the prompt, and it is your duty as the candidate to make it precise!)
3. Understanding (and quantifying if applicable) the underlying objective(s) of the client

These questions are aiming at understanding the initial setting, hence forming a precondition to outline your structure towards answering the core question (the issue tree)!

The later analysis-related questions that you ask while navigating through the case are then aiming to verify the actual relevance of each sub-branch in your tree. So if you have defined and disaggregated the criterion to answer the client's core question in a clean way, all these leater questions follow a this precise "roadmap" as layed out by your tree. These questions then oftentimes also comprise enquiries on current performance metrics (revenues, costs, growth rates etc.), which normally never make sense to be asked in the clarifying questions (before making explicit your structure).

Cheers, Sidi

Hi!

Not sure I understand you correctly, but it seems you are referring to brainstorming questions ("How can we achieve XYZ?", "How should we react to ABC?", "What could be reasons for CDE?").

Here, you always need to start from the definition of your focus metric. If the question is "How can we react to the entry of a new competitor?", then you first have to align on what your objective is - what do you worry about? If it is profit, then you start your logic tree with profit and then break it down into its components with a logic tree. Then you think through, whether and how the competitor entry could negatively affect each branch of your tree (hence, how would the new competitor threaten your profits?). Once you have done this, then you can develop ideas how to prevent the effect of the competitor entry on each of the subdrivers of your profit.

I hope this helps!

Cheers, Sidi

Hi,

There are typically 3 stages of brainstorming potential solutions to a problem during McK interviewer led cases:

1) Prepare a long list of potential solutions to a problem

You need to create a MECE list of relevant ideas, which can solve the problem. Ways to approach:

• Zero drafting - this technique helps establish what you currently know and get your initial ideas out of your brain and onto paper
• SCAMPER technique
  • Substitute - take a part of the product, service or process etc. that you could replace with another to see whether it will result in improvements, such as efficiency gains
  • Combine - one idea might not work alone, but you could combine several ideas, processes or products into one more efficient output. A great example for a combination of two different products are cell phones with an integrated camera
  • Adapt - an idea that worked to solve one problem could also be used to solve a different problem. An example for the successful adaption to a new situation is Netflix. The company started out in 1999 as a DVD rent provider, but they quickly realized that the future belongs to online streaming and changed their product
  • Modify - Changing part or all of the product or process, or distorting it in an unusual way
  • Put to another use - put the current product or process in another purpose or use the existing product to solve problems. For example, this technique can be used to learn how to shift an existing product to another market segment or user type
  • Eliminate - eliminate inefficient processes with the goal of streamlining them. An example for eliminating is Apple’s approach to not include an optical CD drive in their laptop to make them thinner and lighter
  • Reverse - explore the innovative potential when changing the order of the process in the production line
• Analogy thinking - explore inspiring cases and mix their top features with your industry, to come up with new powerful concepts
• Forced connections - take two unrelated concepts and forge a relationship between them

2) Prepare a shortlist of solutions

You need to select solutions that would be financially adequate, could be achieved in the foreseeable future and do not face any constraints of the client situation.

3) Prioritize solutions

Apply 80/20 rule to select 20% of initiatives that would generate 80% of the upside effect.

Best,

Anton

There is no conflict here actually.

A good structure doesn't need to be rigid - it doesn't have to follow the internal/external, financial/non-financial, or other typical ways. What matters is you capture the key aspects of the issue, which requires you to be flexible and customise as needed.

And the branches in your structure can totally include creative ideas. You just need to get your creativity communicated in a structured way.

Hope it helps,

Emily

Brainstorming creatively in a structured/MECE way when under pressure is one of the hardest things to do.

Let's have a look at a basic example: "how can client X gain market share?". A great start to answering the question would be; "Let's look at ways that X can do this in the long-term vs the short-term", OR "Let's see, in general, to grow a business you can change WHAT you sell (e.g., new product vs. old product) or change WHO you sell to (existing customer segment vs. new customer segment).". This way the interviewer can see that you have a structured mind and that you can also prioritise what really is important. Next, you would create yourself a table with Existing Product & New Product ( on the horizontal axis) VS Existing segment & New segment (on the vertical axis). Then, you start brainstorming ideas into each of the 4 boxes. This way, you will be able to come up with loads of things and the interviewer will be very happy with your structured mindset.

Other examples of dimensions that can be used to encourage structured brainstorming are:

• Existing VS New (applies to customer segments, products, distribution channels)
• Organic VS Inorganic (e.g. when thinking about growth)
• Short-term VS Long-term (e.g. when making a decision that required direct implementation)
• Internal VS External (e.g. when talking about operations)
• Customer-focused vs Non-customer focused
• Revenue-based vs Cost-based

Once you have gone through a few ideas and have structured them into sections/buckets it is good practice to select the best ones according to some parameter. For instance, select ideas which have high impact and high implementability. It is important to note that every case is different and so you must always put a lot effort into customising the answer and prioritising what is most relevant.

Hi!

I have a clear opinion here:

(1) Yes. Always! This is also what is expected from you on the job! There is nothing more dangerous than a young consultant on the team who doesn't properly think before talking to clients. Always moderate it in a way like "Good question. Let me take an instant to think this through and outline which aspects are important to consider here."

(2) No. Never start talking before having thought it through! As such, the question is obsolete.

Cheers, Sidi

Hi,

First of all - McKinsey has both Interviewer and Candidate led cases. Please be prepared for both. Candidate led cases are even harder.

1) Yes. Absolutely, you should take time to make a structure

2) I will add a post re the hypothesis below. Short answer - there is no Hypothesis requirement at McKinsey

3) It's a brainstorming question and you should provide as many ideas as possible. I also recommend structuring your ideas into buckets.

4) Both quantitative and qualitative. Think as broad as possible

Now, on the hypothesis:

First of all - it's not mandatory. I would say - use the hypothesis if you are really good at solving the cases. If not - use the basic approach

There are two ways to use the hypothesis:

First - presenting a structure using the hypothesis. For example, if you are having a PE (private equity) case, you should do the following:

1) Make classic structure (market, company, competitors, feasibility of exit)

2) Make subpoints (e.g. in market: size, growth rates, profitability, segmentation, etc)

3) Present your 1st level Hypothesis:

• - "In order to understand whether we should invest in Company A, I would like to check that the Market is Attractive, the Company is Attractive, the competition is favorable and we have good opportunities for of exit"

4) Present the main 2nd level Hypothesis:

• "In the market, I would like to make sure that the market is big enough and growing;
• In the company I would like to find additional opportunities for growth;
• In competition I would like to check that the market is fragmented enough;
• Finally, I would like to check if we have potential buyers and can achieve desired exit multiples"

Another way to use hypothesis is using the hypothesis to prioritize your analysis:

1) Make a structure: "Problem in sales may be related to Sales Motivation, Sales Strategy, Sales Coverage, and Sales Process:

2) Prioritize a part of the structure based on your knowledge / common sense / available data: "Taking into account that motivation is the core problem of the sales organization, I would like to prioritize this part of the analysis"

Good luck!

I would use the population although it will be very sensitive to many assumptions.
It looks very difficult to make meaningful assumptions in terms of land size.

Cheers
Serhat

What share of her mother’s cost is Ana’s profit?

=> Her mothers costs are 100%. We need to find Ana's Profit relative to those 100%.

Ana’s Profit (relative to her mothers cost) = Revenue - Cost = Revenue - 115% = ???

We can calculate Ana's Revenue by using the calculation formula for her Profit Margin:

Profit Margin = Profit / Revenue
Profit Margin = (Revenue - Cost) / Revenue
30% = (Revenue - 115%) / Revenue
30% * Revenue = Revenue -115%
70% * Revenue = 115%
Ana’s Revenue = 164,29% (rel. to her mothers cost)

This means Ana sells the cookies for 164,29% of the price that her mother paid to prepare them.

Ana’s Profit relative to her mothers cost is therefore: Profit = Revenue - Cost = 164,29% - 115% = 49,29%

Hello,I would start by clarifying what performance exactly means, as this has a huge impact on your approach.

One way of looking at it could be to measure performance as the output of good product per hour. In that case you can follow the OEE definition to structure your analysis at the highest level:

Potential production time (calendar year)
Minus availability losses (breakdowns, waiting time, etc.)
Minus performance losses (minor stops, lower speed, etc.)
Minus quality losses (scrap or re-work product)
Equals the output of good product

You can use this structure as the first level, after which you can easily add a second layer with drivers for each of the losses.

Hope this helps!

Hi Anonymous,

I would always recommend to take an instant to identify all the possible elements of an answer to a specific question. Coming up with immature thinking is far worse than being a bit slow! Speed is usually NOT a very important metric on which candidates are evaluated. However, rigor and in thinking and clearness in articulation DEFINITELY are! So the tradeoff is very clear from my perspective.

Cheers, Sidi

Hi,

Usually, you have brainstorming questions in the middle / end of the case when you should already know a lot about the objective / business industry. Thus you should be asking the right clarifying questions at the beginning of the case:

You should ask the following questions:

1) Clarify the business model. Ask how the company actually makes the money. For several reasons:

1. Even if you think you understand the business model, you need to make sure that you understand it correctly.
2. Some cases have pitfalls related to a business model (re profitability cases with several revenue streams
3. You need to understand the revenue streams to make a proper structure. E.g. if the case is about oil&gas company which revenues are declining, ask if it is Up / mid / down-stream problem. In this case, defining a revenue stream is critical to setting up the right structure. (At the end of the day it may be the decline of snack sales at the gas stations:). In case of telecom company it may be the problem of the core business (wireless) or non-core (landlines, internet)

2) Clarify the objective. Here make sure that your goal is:

• Measurable
• Has a time-framed
• Has / has no limitations

e.g. Should I invest 100k in this business for 1 year if I want to get 15% return?

3) Ask the questions that will help you build a relevant structure and remove ambiguity.

E.g. in the market entry case ask whether we are entering the country organically or non-organically

!!! Finally - do the recap after asking the clarifying questions. Although most of the case books suggest to do it immediately at the beginning of the interview, it makes much more sense to clarify the situation first and then to make sure that you understand everything correctly.

Best!

Hi, a couple tips:

• Always ask if you can take ~30 seconds to structure your thoughts. Just because it's a brainstorm, doesn't mean it shouldn't be nicely structured. Worst case, they say you shouldn't take a break, and you are in the same position if you had not aksed.
• First think in terms of buckets, then specific ideas. For example, if you are asked to brainstorm ways to increase revenue, before you start suggesting ideas like marketing campaign, pricing promotion, etc. - break down the revenue - you can do it in a number of ways depending on the specific case
  • P*Q, then Q--> number of customers x purchases per customer, etc.)
  • Business units - e.g. By division, by geography, etc.
• Read through a lot of cases with brainstorm elements. Also, when you find a brainstorm and want to find more ideas, just do some googling /searches on old preplounge questions to get ideas
• Keep a log of brainstorm ideas from typical brainstorm questions (e.g. ways to increase revenue, ways to cut costs, risks faced, etc.). This is important to actually absorb information you learn and find in different cases.

Hope this helps!

Alessandro