The 3 mistakes that kill experienced hires in McKinsey case interviews

I've seen dozens of smart, accomplished professionals bomb MBB case interviews. Not because they lack business sense — they have more than most MBA candidates. They fail because they make 3 specific mistakes that consultants are trained to spot in the first 5 minutes.

Mistake #1: Jumping to solutions instead of structuring.

In your day job, you're paid to solve problems fast. In a case interview, you're being evaluated on HOW you think, not WHAT you think. When you skip the structure and go straight to "I'd cut costs and expand into new markets," the interviewer writes "no structured thinking" and moves on.

Mistake #2: Using generic frameworks instead of custom ones.

If you open with "I'll use the 4 P's" or "Let me apply Porter's Five Forces," the interviewer has already heard that 50 times today. McKinsey evaluates whether you can build a bespoke framework from first principles. The frameworks from business school textbooks will actively hurt you.

Mistake #3: Not driving the case.

McKinsey uses an interviewer-led format (they control the flow), but they still expect you to have a point of view. Passive candidates who wait to be told what to analyze next get dinged on leadership. You need to recommend what to explore and why — even as the interviewer redirects you.

The fix? Structured practice with people who know the format. Not YouTube videos. Not reading case books alone. Live reps with feedback.

That's exactly what we built OfferReady for. Working professionals prepping together, holding each other accountable, and getting offer-ready faster than going it alone.