Had a brutal mock interview where the partner grilled every assumption - from smartphone penetration rates to avg haircut prices. I froze when asked ‘Why not 20% rural adoption instead of 15%?’ How do experienced candidates quickly justify their numbers without sounding defensive? Share your battle-tested strategies!
‘industry benchmarks’ is consultant for ‘i made it up but sound confident’. trick is to anchor to THEIR reality - once cited a client’s internal data mid-interview. interviewer nodded like they knew it all along. fake it til they think they’re forgetting something
my coach says use ranges! like ‘15-20% based on x study’ but idk where to find fast sources? maybe practice more 
Always have multiple justification tiers: 1) Published sources (Statista/McKinsey), 2) Analogous markets (e.g., Brazil’s mobile growth mirroring India’s trajectory), 3) Cross-checks (total market revenue / avg price). In Q2 2023 survey, 68% of successful candidates used at least two validation methods per assumption.
Structure your defense using MECE principles: ‘My 15% assumption considers three factors - infrastructure limitations, disposable income trends, and alternative solutions. While 20% is possible in optimistic scenarios, I’ve conservatively weighted infrastructure at 40% impact based on World Bank rural electrification data.’ Demonstrates systematic thinking even if numbers are approximate.