Case Interview Secrets (P1)

Want to work at a consulting firm like McKinsey & Company? Then you should know that to land a job at McKinsey is 10 times harder than to get accepted to Harvard University.

The good news, though, is that there are smart ways to crack the case interview. Victor Cheng, former McKinsey consultant and case interviewer who aced an incredible 60 out of 61 case-interviews, gives you the interviewer’s guide on how to crack the case interview and get job offers not from just one but from multiple consulting firms.

DIAGRAMS

TOP 20 INSIGHTS

1. Recruiters seek candidates who already behave like consultants. Consultants speak for the firm when they engage with a client. Therefore, firms want candidates who pick their words carefully and can factually back every single statement.
2. Besides great analytical and problem-solving skills demonstration, candidates must be able to present their conclusions in a client-friendly manner. This is because clients only accept the recommendations that they can understand. Often, interpersonal skills make the difference between a job offer and a final-round rejection.
3. Interviewers prefer slower candidates who employ a consistent, repeatable process over faster ones who use unrepeatable methods. It is easier to coach for speed, but difficult to improve accuracy.
4. The case interview closely simulates the everyday experience of a consultant’s job. Case interviews involve estimation questions because clients ask them every day. If a candidate doesn’t enjoy the interview preparation process, chances are they might not enjoy the job either.
5. Case interviews are hypothesis-driven, not framework-driven. The hypothesis determines the choice of framework. A candidate who masters the critical reasoning behind issue trees performs better than the one who mechanically applies frameworks. The thoughtless application of standard frameworks is a red flag in interviews.
6. If the complete issue tree is shared right at the beginning, it gives the interviewer a sense of how the candidate approaches the problem. If a candidate doesn’t do this, the interviewer may conclude that the candidate has not created an issue tree.
7. “Drill Down Analysis” is a systematic method to visit branches and sub-branches in an issue tree. At each branch, the candidate analyzes relevant data to prove or disprove the branch. If a branch is proven false, the candidate revises the hypothesis and creates a new issue tree. The process ends when a hypothesis is validated.
8. In a client interview, a consultant doesn’t spend the majority of the time on the client’s problem solution. Instead, the time is spent on the isolation of the causes behind a client’s problem. 75% of the time is spent on problem definition. Candidates must never propose a solution until they are confident of having identified and isolated the problem.
9. Candidates often struggle to manage notes. A highly effective way is to keep exclusive sheets for crucial information like hypotheses and issue trees and use separate sheets for calculations. When a branch is eliminated, candidates can show the updated issue tree to the interviewer.
10. Synthesis is a specific way to communicate progress: state an action-oriented conclusion, three supporting points and restate the recommendation. Synthesis is used at the end of the case and when branches are switched in the issue tree. Interviewers highly value this skill in candidates.
11. Smart candidates use their time efficiently and don’t memorize a dozen frameworks. Mastery of just three general frameworks — Profitability, Business Situation and Mergers and Acquisitions — is sufficient to tackle 70% of case interviews. Creation of custom issue trees will take care of the rest.
12. The Business Situation Framework is useful when you need to better understand the qualitative aspect of the context, refine the hypothesis and find efficient ways to test it. The four main branches are Customer, Product, Company and Competition. They can be utilized to analyze cases like a new product introduction, a growth strategy development or a new market entry evaluation.
13. The “Candidate Led Case Interview” is an open-ended format designed to simulate how consultants approach open-ended client problems. This format has been around for decades and every other format is just a variation of this. Therefore, when this format is mastered, the candidate is empowered to excel in all the others.
14. To buy a valuable minute at the beginning of an interview, a candidate can repeat the client’s question back to the interviewer and ask questions to clarify the client’s objective. This gives a candidate time to deal with panic and think of an initial hypothesis.
15. Totals and averages always lie. The ability to segment numbers into components is critical for analysis. The best way to understand the implications of a unit is to compare it to a previous time period and the industry norms.
16. In the “Interviewer Led Case” interview, the interviewer chooses which parts of the case are essential and asks specific questions. This can lead to a lot of abrupt switches in the case flow. Excellence in this format depends on the mastery of the issue tree and synthesis. McKinsey has moved almost exclusively to this format.
17. In the “Group Case” interview, candidates are expected to work with competitors to solve a case. Interviewers use this format to identify how candidates collaborate and build on the ideas of others under pressure.
18. In a “Presentation Case” interview, candidates are evaluated on presentations created with given data sheets analysis. The presentation structure follows the synthesis format: groups of slides for the actionable conclusion, three key insights and restatement of the recommendation. Each slide has a data table or chart, labels and a title that conveys the critical insight.
19. To train for a case interview is more like to prep for a bicycle race than to take an exam. This is because it doesn’t test what candidates know but rather what they do under pressure. Candidates who get multiple offers have both case interview knowledge and habits to apply it.
20. The only way to get multiple job offers is a disciplined practice. 90% of Cheng’s students who got an offer practiced for 50 to 100 hours. Candidates who clear the top three firms have participated in an average of 50 practice cases. The best way to train is to first watch an expert give a case interview and replicate best practices in mock interviews.