Kareem Zaki is a General Partner at Thrive Capital. We cover why being a generalist allows for more creative investment ideas, how Thrive spotted "category-defining" companies like SpaceX and OpenAI early, and how to solve some of the biggest problems in the healthcare industry.
Principles & Lessons:
1) Focusing on “category-defining” rather than merely good. Kareem repeatedly stressed that “if you’re fine investing in good and great companies… it actually dilutes your thinking” when aiming to find true outliers. He explained that Thrive intentionally devotes all of its attention and diligence to the rare businesses “really shaping not just tech, but every industry.” As he put it, “Small ideas have lots of competition,” so a sharper lens is needed to identify breakout companies with “a big vision” and strong market pull.
2) Pairing a creative vision with concrete steps. When asked what distinguishes the founders he backs, Kareem cited those who rewire one’s perspective of an industry but also present “the clear steps to go do that.” He gave examples like SpaceX or Formation Bio, companies that start with an apparently radical mission—“to go to Mars” or “being a full-stack pharma company”—and show well-planned phases. As he put it, “A big vision without a plan is just a fantasy.”
3) Concentrated investment drives genuine partnership. Kareem insisted that “concentration drives conviction,” allowing Thrive to become “the most meaningful partner” to the companies it backs. “If you have 1,000 portfolio companies,” he observed, “it’s just impossible” to offer the kind of “in the trenches” assistance founders need. By limiting the number of investments, Thrive binds itself closer to these teams and can drop in with, as he said, “one or two of our leaders… embedded in companies, almost committed.”
4) Building alongside entrenched systems in healthcare. Kareem believes that innovators must “meet the system where it is,” rather than disregard it. He referenced Oscar’s need to become a “full insurance company,” or Cadence’s decision to work within fee-for-service and partner with existing health systems. As he emphasized, “It’s intimidating to build a new pharmacy benefit manager… but that’s the only way” to achieve tangible patient impact. This approach, though capital-intensive and complex, is key to solving real-world healthcare problems rather than building small add-ons.
5) Avoiding “fool’s gold” by looking past superficial traction. While strong growth can tempt any investor, Kareem clarified that sound fundamentals and market structure matter more. “Revenue doesn’t mean you’re solving a problem,” he said, warning that a seemingly high-growth startup may operate in a flawed or low-quality market. In his words, “You can’t escape the genetics of the business,” so discerning genuine tailwinds, durable margins, and strong retention is crucial for long-term success.
6) Using data and firsthand observation to see beyond the pitch deck. Kareem spoke about the advantage of being a “life-cycle investor,” explaining that seeing companies “multiple times” reveals whether they’re merely “pretty in a PowerPoint” or show real momentum, even when “things aren’t going perfectly but the metrics look amazing.” He underlined that thriving businesses often look “busted but booming,” meaning they have internal chaos yet still experience overwhelming market demand, which signals product-market fit better than a polished pitch.
7) Combining product imagination with operational reality. Kareem believes that, at any stage, investors should “dream with founders” about a 10-year horizon while maintaining the analytical discipline to evaluate data. He recalled that at Ramp, for instance, Thrive’s team explored “how customers use your product, where’s the product going to evolve from here,” instead of just focusing on payback and LTV-to-CAC metrics. As Kareem noted, “Founders don’t change who they are just because they’re Series D… they started the company because they wanted to solve a problem.”
8) Recruiting team members who share a “maverick mentality” and range. At Thrive, “everyone’s heroing it,” so new hires must show initiative, personal drive, and curiosity. “If you’ve always done the default thing in your life,” Kareem said, “you’re probably not a fit,” because the firm mirrors the founders they back—those bold enough to disrupt entire industries. Kareem also referenced a love for generalists: “People who are multidimensional and connect worlds in different ways” can better spot and support the few companies that will truly “transform every industry.”
Transcript