Top 15 Mistakes in Case Interview Preparation

As someone who has personally helped over 100 candidates land offers at MBB (McKinsey, BCG, Bain), I’ve identified 15 common mistakes that hold people back from getting offers. By understanding and avoiding these pitfalls, you can set yourself up for a much smoother interview experience and greatly increase your chances of success.

Before the Application

1. Lack of Clear Goals: Many candidates don't take the time to define their goals or understand why they want a career in consulting. This lack of clarity leads to a lack of focus during preparation and can hurt motivation in the long run.

During the Application Phase

1. Applying to Just One Company: One of the most common mistakes is focusing all efforts on one company rather than applying to multiple firms. This limits your chances of success and puts unnecessary pressure on a single application.

2. Not Using LinkedIn Networking: Many candidates don’t leverage LinkedIn networking to maximize interview invites. Building connections and getting referrals from consultants can significantly improve your chances of getting an interview.

3. Poorly Structured CV and Cover Letter: Not paying attention to the details of your CV and cover letter can lead to immediate rejection. It's crucial to tailor these documents to each firm and role, highlighting relevant experience and achievements clearly.

During the Preparation Phase

1. No Systematic Approach: Instead of following a structured preparation plan, candidates often read random books and solve cases from casebooks without clear progression or focus. This approach lacks direction and often leads to burnout or slow improvement.

2. Solving Each Case from Scratch: Many candidates try to approach each case individually without using proven case-solving frameworks or algorithms. This slows down progress and makes it harder to build confidence.

3. Treating All Cases the Same: Candidates often don’t differentiate between different types of cases (e.g., M&A, pricing, growth) and fail to develop specific algorithms for each. A one-size-fits-all approach doesn’t work for all case types.

4. Ignoring Industry Knowledge: Failing to study different industries reduces your ability to contextualize cases. Having a basic understanding of industries like oil & gas, retail, or banking helps you approach cases more effectively and impress your interviewer.

5. Skipping Math and Graph Preparation: Overlooking the importance of practicing case math and graph interpretation is another common pitfall. Many candidates underestimate how frequently these skills are tested during interviews.

6. Not Preparing Fit Stories in Advance: Candidates often don’t pre-prepare their fit stories based on MBB criteria, leading to less compelling responses during the fit portion of the interview.

7. Solving Only Easy Cases: Many candidates practice only easy cases with partners, avoiding challenging MBB-level cases. This can lead to overconfidence and a rude awakening during actual interviews with top firms.

8. Not Tracking Feedback: Candidates frequently fail to collect and organize feedback from their case practice. Without a central place to track improvements and areas for growth, it’s hard to see consistent progress.

9. Ignoring the Differences Between Candidate-led and Interviewer-led Cases: Not understanding how to adapt your approach to both types of interviews (candidate-led vs interviewer-led) can cause issues during real interviews.

During the Interview

1. Overestimating the Importance of the Interview: Many candidates let nerves take over because they overvalue the significance of one particular interview. This heightened stress can lead to poor performance.

2. Failing to Build Rapport with the Interviewer: Establishing a connection with the interviewer is key to success. Many candidates focus so much on solving the case that they forget to engage with the interviewer on a personal level.

Avoiding these mistakes can make a significant difference in your preparation and interview performance. If you're ready to take your case prep seriously and want to ensure you’re on the right track, text me a message. We can discuss your situation and start building your tailored prep journey today!

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