Do Solo Founders Really Underperform?

There’s a whole body of lore around founders and co-founders. That you need one. How to find the right match. How to split the equity. When to walk away. “We’d want to see a co-founder” is one of the most confidently asserted rules in early-stage investing, and one of the most often repeated with no evidence attached. So we went looking for something more solid.

What the research says

The picture is a lot less tidy than the advice.

• Team-founded startups tend to raise more early capital. One of the more replicated findings. But it measures funding, which is partly a mirror of investor preference, not an independent read on company quality.¹
• Survival and growth effects are inconsistent. Across studies, once you control for prior experience and access to capital, the “solo penalty” shrinks and sometimes disappears. Roughly 1 in 5 billion-dollar startups were solo-founded, often by folks with stronger track records.^{2, 3}
• Co-founder conflict is a top failure mode. The deepest research on founder dynamics, drawn from nearly ten thousand founders tracked over a decade, is blunt on one point: the breakdown of the relationship between co-founders is among the most common and most destructive early failures. That body of work, by Noam Wasserman, is where the warning actually comes from.⁴ A bad co-founder is worse than none.⁵

Here’s the honest version. Startups are hard, and they can be brutally lonely. The one thing every startup needs is the right combination of skills, and it’s genuinely rare to find all of them in a single person. That’s the real case for a co-founder. Not a box an investor wants ticked, a capability you’re actually missing.

The real variable

So the evidence points away from headcount and toward two things: complementarity and durability. A second founder helps when they add a capability the company actually needs and can’t easily hire for yet, and when the relationship can survive real stress.³

We’ve seen this up close, and it’s the part the spreadsheets miss. Deep co-founder trust is close to the whole game, precisely because relationship failure is so common. The pair who can be genuinely vulnerable with each other, and who bring truly complementary skills, has a huge advantage. Bolting on a co-founder to satisfy a pattern-matching investor, with someone you’ve never been through anything hard with, imports the exact risk the research keeps flagging.⁴

What we tell founders

When I started my own company, I started solo, then brought on co-founders because I needed the help. That’s not unusual, and it isn’t a weakness. Finding people whose skills complement yours lets you move faster, and I’m grateful I did.

But I also tell solo founders this: it’s not really about the title “co-founder.” Sometimes wanting to stay solo is a control question in disguise. What actually matters is having someone genuinely in it to win it with you, a founding engineer, an early teammate, a partner who owns the outcome the way you do. That commitment is the advantage, whatever you call it.

So if you’re solo and it’s working, “get a co-founder” is not a data-backed mandate. Solve for the missing capability and the missing conviction. Sometimes that’s a co-founder, sometimes a founding engineer, sometimes an advisor. And if you do bring someone on as a co-founder, spend more time on the equity split, the roles, and the vesting than on the pitch. That’s where the evidence says the outcome actually gets decided.^{4, 6}

References

1. Esen, T., Dahl, M. S., & Sorenson, O. (2023). Jockeys, Horses or Teams? The Selection of Startups by Venture Capitalists. Journal of Business Venturing Insights 19, e00383. Firms with more and better-educated founders are likelier to be funded, and larger, higher-quality teams raise more still. Author copy · ScienceDirect
2. Tamaseb, A. (2021). Super Founders: What Data Reveals About Billion-Dollar Startups. PublicAffairs. About 1 in 5 billion-dollar startups were solo-founded, often by founders with stronger track records. superfoundersbook.com
3. Eesley, C. E., Hsu, D. H., & Roberts, E. B. (2013). The Contingent Effects of Top Management Teams on Venture Performance. Strategic Management Journal 35(12), 1798-1817. A team’s effect on performance is contingent on strategy and environment, not a fixed headcount premium (2,067 firms). SSRN · SMJ
4. Wasserman, N. (2012). The Founder’s Dilemmas: Anticipating and Avoiding the Pitfalls That Can Sink a Startup. Princeton University Press. Co-founder relationship and equity decisions are among the most common and most destructive early failures; friend and family teams are less stable. Princeton University Press
5. De Wit, F. R. C., Greer, L. L., & Jehn, K. A. (2012). The Paradox of Intragroup Conflict: A Meta-Analysis. Journal of Applied Psychology 97(2), 360-390. Across 116 studies (n≈8,880 groups), relationship conflict is robustly negative for group performance and satisfaction. PubMed · APA
6. Hellmann, T. F., & Wasserman, N. (2011). The First Deal: The Division of Founder Equity in New Ventures. NBER WP 16922; Management Science 63(8), 2647-2666 (2017). Quick, equal “handshake” equity splits track avoided hard bargaining and lower valuations (1,476 founders). NBER · Management Science

Full source library for this brief: the Research Library.