That depends mainly on the seniority, i.e. how experienced the hires are.
I coached 2 partners of a tier-2 boutique consulting firm in Europe for transferring to McKinsey partner-level position. This process consisted of 16 interviews spread over several months, and the typical case interview as you know it is not even part of the recruiting process. So fully individualized interview scheme for that top-level hires.
If you rather think about a few years of industry experience - cases in first rounds tend to be the same, but expectations are obviously significantly higher. Not only in analyitcal aspects, but much more from a top-down and communications point of view.
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