I would not recommend taking more than 1 minute. You should give a structured answer providing a couple of recommendations and ways of how to minimize risks.
Besides, you might not even get extra 30 seconds for preparation so be ready to provide a full answer right on the spot.
You should only take about 15-30 seconds to prepare it and about 60 seconds to deliver it.
Remember, you may ask to prepare and the interview responds "sorry, the CEO is calling right now, you don't have time", so be prepared throughout the case with a recommendation!
First of all, here are the general ways to provide the recommendation:
The typical structure is the following:
The problem is that In many cases, you can't provide a definite answer since you don't have enough information
Consultants may be testing several things:
Imagine a case when you have to make a decision whether a PE fund should acquire a company. You make a proper structure (Market, Competitors, Company, Feasibility of Exit) and in 25 min of a case, you've managed only to go through the Market and Competitors branches of the analysis. What will be your recommendation?
In this case, you have to provide a Soft Recommendation:
30 seconds, maximum a minute. You want to just give your answer, supported by 3 arguments or insights. Then give a few recommendations on what to assess next to substantiate the finding. That's it.
You should target one minute to deliver a conclusion. The interviewer may give you a shorter time constraint (eg 30 seconds), thus you should also practice for shorter versions.
As a structure for the conclusion, I would recommend the following three steps:
1) Repeat the objective. This will ensure you are answering to what is relevant for the case. Forgetting to repeat the objective is one of the most common mistakes candidates do in the conclusion and can lead to answer the wrong question. As an example:
2) Provide an answer-first solution. You don’t have to present everything you discovered in the case at this stage, only the main conclusion and its supporting factor. If the conclusion is not clear 100% as you have not analyzed all the elements of your structure to derive a definite yes or no, you can provide a preliminary answer based on the elements you have identified.
3) Provide risks / next steps suggestions. You should always have next steps/ risks in your conclusion. You can refer to the elements present in your structure that you did not have time to cover or to risks that emerged during the case: