I see a lot of recruiting-brochure takes on McKinsey culture online, so here's a ground-level one from someone who was there for three years and voluntarily left.
I'm not here to trash the place. There are genuinely smart people, genuinely interesting problems, and the training is real. But I want to give you the unfiltered version on WLB because that's what I wish someone had given me.
Travel: In client service roles (most of what McKinsey does), the Monday-Thursday travel schedule is not a rumor. For me it was consistent across 2.5 of my 3 years. You fly Sunday night or Monday early, you come home Thursday night, you catch up on everything else Friday. Weekends were nominally yours but the culture of finishing deliverables before Monday meant they often weren't. If you have a partner, family obligations, or medical needs that require a predictable location, this is a serious constraint, not a manageable inconvenience.
The staffing model: You don't choose your client. You don't always choose your team. For the first 1-2 years especially, you're staffed to whatever needs bodies. Some engagements are genuinely interesting. Some are 5 months of procurement cost reduction for a company you've never heard of. Both are called "McKinsey work."
The good parts that are actually good: The feedback culture is unusually rigorous. I got more structured performance feedback in my first year at McKinsey than in four years at my prior role. The alumni network is legitimately helpful. And the problem-solving muscle you build is real. I use it constantly.
Why I left: I hit 32 and realized I wanted to build something, not advise on it. There's a type of person who thrives in consulting long-term. I'm not that type. I don't think that's a character flaw in either direction.
If you're interviewing at McKinsey, ask specifically about which practice and client sector you'd be in. The lifestyle variation by sector is significant.