When reflecting a completed case, how "deep" should the issue tree branches be?

Question

I'm working on improving my structuring skill. I'm wondering when I am doing a reflection on the case I've done and redoing the case structuring part, how “deep” should the issue tree branches be?

Some coaches mentioned the structure should be “as deep as possible”, in some cases maybe even 4-5 layers, since nowadays case interviewers drill down the issue tree deeply.

Would doing this practice help to improve structuring skills? Or, finding the “key questions” to answer is more important than trying to develop a comprehensive issue tree which has 4-5 layers? Please advice some effective tips to improve structuring skills and the ability to flexibly structure any type of cases.

Answer 1

Don't do 4-5 layers. Do 2-3 layers (considering the points mentioned by Ian) and ask if the interviewer wants to go deeper on anything.

Most likely he won't, and you will save time (and avoid unnecessary mistakes). But if he does, then go deeper.

Answer 2

4-5 layers is too much, I would stick to 2 (with detailed commentary) or 3. Taking the time to think through the framework in a completed case is certainly a useful exercise, but it also enables you to come up with much more material than would be optimal to use in a case. In a case interview, you should be taking around 1-1.5 minutes to think through and map out your framework, and then 2-3 minutes describing it to the interviewer. So you really don't get much time to delve into 4-5 layers of detail.

In light of this, I would feel free to do the practice you outline to improve your structuring skills, but sift through all the ideas you get to end up with a concise, MECE framework of 2-3 layers or so. If you are looking to improve your frameworks and structuring, I would also recommend practicing doing frameworks in timed conditions. Read a case prompt, and then draw out the framework as if it were an actual interview (make it MECE, don't take too much time, etc.). Then, compare your framework to the solution (or, if there is no solution, take time to think through it in more detail), and see what you could improve for next time.

Answer 3

Your question is too generic. The answer to it is very case specific.

4-5 layers is too deep regardless. If you are having to drill 4-5 layers then you are probably keeping your structure way too tight. 3 layers is generally a very good maximum.

Happy to take a look at some of your examples and provide you further guidance - feel free to send me a message with your specific cases.

Answer 4

Hi there,

The answer here is truly case and company-specific. As in McKinsey prefers deeper structure, but also different interviewers have different preferences. Furthermore, depending on the case, the structure might be quite obvious/flat, or quite complex/deep.

That said, 4-5 layers is certainly too much. My advice is generally 2-3, but the most important thing here is that you have a structured, MECE, objective-driven approach to solving the problem in the context of the company + case.

Feel free to shoot me a message - I have a sample video of a strong structure/framework I can send your way.

Answer 5

The deeper you go the harder it could become to analyse and calculate as you will have to make more and more estimates/hypothesis/calculations. While there isn't a magic number for how many layers, to keep things manageable and avoid analysis paralysis, 3-4 down seems reasonable. But be ready to adapt this based on the case prompt and based on common sense.

Answer 6

Hi!

It is definitely a skill you need to master!

I think an important thing to consider here is timing. If you can get 4-5 layers down your structure and communicate efficiently and effectively why not?

In general, 2-3 layers are enough for the initial structure. Do not underestimate the importance of top-down communication and MECEness!

Hope this helps.

Best,

Anto

Answer 7

Deeper/ more doesn't always mean better in consulting :)

To re-iterate what other coaches, 2-3 layers is usually sufficient. The top layer (first layer of questions/ topics) should directly help answer the main question/ address the objective of the case.

Do let me know if you need support with formulating robust issue trees. I specialize in this via a very intuitive approach.