Case interview hypothesis
If you're using our McKinsey Case Interview Training Programme you might have noticed that we don't use hypotheses when solving cases. And if you're using the BCG & Bain Case Interview Training Programme, you might have noticed that we only use hypotheses in certain cases. Let us explain why in detail here.
Some coaches such as Victor Cheng from caseinterview.com use a hypothesis all the time. But doing this in practice can feel quite artificial during your case interviews.
For instance, if you are trying to decide what type of new beverage Coca-cola should launch next year, using a hypothesis is possible but does not add a lot of value. You could start by saying something like: “I’m going to hypothesise that Coca-cola should launch a new diet orange juice next year because customers are more and more health conscious”. But this would be nothing more than a wild guess at the beginning of a case. This is why a lot of candidates are uncomfortable using a hypothesis driven approach.
In real life, the main situation when consultants use a hypothesis is when they are looking for the root-cause of an issue. For instance, when they are trying to understand why the profitability of a company has decreased. The root-cause could be many things: lower price, lower volume, higher variable costs, etc.
Using a hypothesis in these cases is actually very helpful because it enables consultants to stay really focused and to methodically test all the potential sources of the problem until they find the one that’s actually causing the problem. Our recommendation is therefore to do the same in your cases and to only use hypotheses in framework exploration questions where you are looking for the root-cause of an issue.
Root-cause cases are frequent in candidate-led cases, but not so much in interviewer-led cases where the interviewer is taking you from question to question. This is why we use hypotheses in some BCG & Bain cases in our programmes, but not our McKinsey programme.