As suggested by David Garvin, learners gain diagnostic and persuasive skills.
“Cases and case discussions thus serve three distinct roles. First, they help students develop diagnostic skills in a world where markets and technologies are constantly changing. “The purpose of business education,” a business-school professor noted more than 70 years ago, “is not to teach truths…but to teach men [and women] to think in the presence of new situations.” This requires a bifocal perspective: the ability to characterize quickly both the common and the distinctive elements of business problems.
Second, case discussions help students develop persuasive skills. Management is a social art; it requires working with and through others. The ability to tell a compelling story, to marshal evidence, and to craft persuasive arguments is essential to success. It is for this reason that the business school puts such a heavy premium on class participation. Beyond grading, students also receive regular feedback from professors about the quantity, quality, and constructiveness of their comments.
Third, and perhaps most important, a steady diet of cases leads to distinctive ways of thinking—and acting.” (David Garvin, Making the Case, https://harvardmagazine.com/2003/09/making-the-case-html)