How to Conduct Mock Case Interviews
When conducting mock interviews, make sure you’re practicing with someone you trust.
Okay, let me rephrase that — make sure you practice with someone who can hold you accountable. For instance, I used to case all the time with my room-mates and close friends.
Here’s the problem — we didn’t take it seriously. It was too easy to goof around, have fun with the process, and treat it lightly.
To be perfectly honest, it was good practice to case in a more light-hearted manner. It helped me prepare to be more casual and upbeat in my actual cases, and treat my interview as more conversational and engaging than stiff and formal.
That being said, it was absolutely terrible for my case discipline.
When I asked mentors and upper class-mates to start casing me, I immediately picked up the slack. Their time was incredibly valuable, and I didn’t want to squander it without giving practice all I got.
Mentors and upper class-mates, having gone through the process, are also quite possibly the best sources of advice and feedback you can get, short of casing with strangers working in consulting full-time. Many firms do have case interview workshops, and some even offer first round candidates 1:1 training with one of their consultants to walk through a mock case. Use these resources! Talk to any mentors or upper-classmates in clubs and student org’s you are part of to case you!
On that note, to properly evaluate case interview performance, here are some sample rubrics that can help you think about structuring feedback and areas for improvement.
First — the opening question. This is your first impression, your chance to impress your interviewer by asking key clarifying questions. Some cases jump straight to the point by asking upfront “how should the client move forward.” Other cases stop, and then the interviewer will pause to allow you to ask questions and recap the case. In the case of the latter, don’t worry too much about this scoring key. Focus on asking clarifying questions and understanding the situation.
Second — the framework. You will spend the next 30 seconds or so quickly jotting down your framework for tackling the overall problem. The key is to provide 2 levels of analysis in each bucket (re: for revenues dig into prices/volumes then dig into segments by products / customers / geographies / etc.). Some case guides say top candidates have a ‘hypothesis’. This is something I didn’t really explore in my guide, because most candidates unconsciously use hypotheses anyway.
Anytime you are asking for additional information, you are operating under a hypothesis (re: this data I’m asking for is key to solving the case). Besides, you won’t even be close to having all the context you need at the start of the case to suggest a hypothesis. That being said, you can certainly commit to a hypothesis (re: based on what we know, it appears increasing costs is driving our client’s decline in profits), and then go the extra mile for prompting the interviewer if the client has any data on costs over the past 5 years and go from there.
In any case, the key here is to provide a highly structured, customized framework that is MECE and hits all the potential question areas in the case. On a side note, a real power move is to flip your paper around, look your interviewer in the eye, and walk them through your framework as they get to follow along by looking at your work. While this won’t be feasible given virtual recruiting and COVID-19, when in-person interviews become a thing (sigh, but maybe that’s never given the current state of affairs) keep this strategy on the back of your mind!
Third — creative questions. Creative questions can happen in any order, such as directly after the framework or right before the synthesis (more common). Because creative questions are unstandardized, I can only tell you that the key mistake here is that candidates don’t tie back a specific question to the overarching question posed at the start of the case. Contextualize your analysis, provide the “So What,” and always loop back to the original problem posed.
Fourth — quantitative questions. In a case, it is unquestionable that you will, at some point, be forced to calculate and quantitatively evaluate which strategy the client should take. Here are my quick thoughts — you are allowed one mistake per case, but you HAVE to immediately catch said mistake and fix it once an interviewer corrects you. You should also never spend more time in silence than you do while talking and walking your interviewer through your math and thought process. As soon as you’re given the problem, walk your interviewer through your strategy.
Develop the formula needed to solve the problem (re: market sizing top-down formula, break-even equation, etc.) and verbalize it to your interviewer. Once you get the thumbs-up that you’re on the right track, do the math aloud. Especially as case interviews are becoming remote, it’s more important than ever to be able to clearly verbalize your thought process. If you don’t, your interviewer is 100% going to be lost in the case sauce, and they won’t be able to follow along with you in their own case.
Fifth — the synthesis. Your synthesis needs to be ready-to-go on the spot, and should not last any longer than 1 minute. A little caveat at the end — a perfect score should include not only the elements below, but also a quick recap of possible risks present in your recommendation.
Some other things to evaluate case interviewers on include:
Overall Structure: A candidate’s ability to embed structure in every question in every prompt, as well as his or her ability to manage the flow of the case without getting lost and confused and connect certain parts of the case back to other sections
Overall Problem-Solving: A candidate’s ability to quickly solve quantitative and qualitative problems, who is quick to realize they made a mistake and correct it without being told, and is focused on the overarching question and does not get easily sidetracked
Overall Communication: A candidate’s ability to provide concise, articulate responses to each question, one who is confident but easy to work with and maintains a positive attitude even when under pressure, and is persuasive and compelling
When providing feedback, you should do so on a line-by-line basis. Provide feedback on structure, on the second question, on the third, on the fourth, on the synthesis, vice versa. Then provide macro-level feedback — this includes structure, problem-solving, and communication. Record your interviews so you can play them back and see where you screwed up / where you are weak.
And be sure to both be cased and case others! Being cased is great interviewing experience, but casing others puts you in the shoes of the interviewers themselves. You’ll begin to see the little things candidates can do during a case interview that make interviewers’ lives so, so much easier, and you’ll begin to see how you can adopt these best practices when it’s your turn to be cased.
This is also great advice beyond consulting in general — when you interview others, you will begin to pick up key practices that separate bad candidates from good candidates from exceptional candidates.
This is true in casing as well as behavioral interviews and other forms of technical interviews as well.