How do you argue 'Why IB' if you have no IB internship, only audit, consulting, or corporate-finance internships?

Bridge from adjacent experiences. Audit gives financial statement discipline, consulting gives problem structuring, and corporate finance gives company-side decision context. Then explain why banking is the next step: faster transaction exposure, valuation, capital markets, and deal execution. Show you understand the gap and have prepared through technical study, clubs, case work, or networking.