I had 5 co-founders. Here, I said it.

But I didn't choose 5 co-founders because I wanted 5. I chose them because I was made to believe that:

Every time it didn't work, I didn't question the advice, I questioned my judgment in picking people.

I did that 5 times, and 5 times it fell apart.

Five relationships, five different people, five different reasons on paper. But the pattern underneath was the same: vision drifting apart, or personal circumstances changing, and instead of building the company, we were negotiating who was right.

By the fifth time, I stopped asking who the right co-founder was and started asking why I assumed I needed one at all.

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Here's the part that took me longest to admit. I wasn't looking for a co-founder because the business needed one. I was looking for one because my own confidence had been quietly worn down by everyone around the table who wasn't me.

VCs asking "who's your technical cofounder" before they'd even heard the idea. Accelerators structuring entire programs around the assumption that a solo founder is missing something. Enough rooms like that, and you stop hearing it as opinion, you start hearing it as fact. I'd let other people's conviction about how startups look replace my own.

That's what I want other founders to sit with: whose voice are you listening to when you make that call?

Rare Founders is three years old now. It's not a unicorn, and that's not the only bar that matters. What it is: a community of 25,000-plus founders, investors, and operators, running the largest demo day in London, with a brand people in the UK startup world actually trust. I built that by myself.

It's the first time in my life I listened to my own read on a situation over the outside validation loop I'd been running on for years. No co-founder search, no hedging by bringing in a partner to share the risk or the credit, just building it, being wrong about parts of it, and fixing those parts, on my own judgment.

I'm not claiming going solo was definitively right, I don't have the counterfactual. But I know how it compares day-to-day, because I've lived both versions. The comparison isn't close.

A meaningful chunk of the energy in a co-founder relationship doesn't go into the business, it goes into managing the relationship itself. I've sat in arguments about the next feature, or the exact wording of a marketing message, that had nothing to do with what was right for the customer. It was two egos trying to win, because that's what happens when two people have full authority over the same decision and no tiebreaker. You're not debating the feature anymore, you're debating who gets to be right, dressed up as strategy.

That time never touches execution, and it compounds. Wasserman's data puts co-founder conflict as a contributing factor in roughly 65% of high-potential startup failures. CB Insights independently ranks team disharmony among the top causes of startup death. I don't read those numbers as abstract anymore. I read them as every ego argument I ever had over something that should have taken ten minutes to decide.

Going solo doesn't remove hard decisions, it removes the layer sitting on top of every hard decision, where you also have to win an argument before you're allowed to execute.

Ask any accelerator, VC, or experienced founder, and you'll get the same answer: don't go alone. What's not true is the part implied along with it: that going with a co-founder is the safer, more proven path.

Y Combinator only accepts solo founders in about 10% of its cohorts. First Round Capital's own portfolio data shows multi-founder teams outperforming solo founders by 163%, but that's a VC's own portfolio, teams get funded more easily when investors prefer them. That's not proof teams build better companies, it's a self-fulfilling prophecy dressed up as a track record.

Separate the funding data from the survival data and the picture changes.

Jason Greenberg (NYU Stern) and Ethan Mollick (Wharton) tracked 3,526 crowdfunded ventures and found solo-founded companies survived longer and generated more revenue than founder pairs. A Crunchbase-based analysis of exits found 52.3% of successfully exited startups had a single founder, dropping to 45.9% among companies that had raised over $10 million, the same VC-preference gap again. The honest version isn't "co-founders make you more likely to succeed," it's "co-founders make you more fundable, and separately, more likely to implode."

Carta's Solo Founders Report found something that undercuts the caution itself: once a solo founder does convince a VC to invest, dilution and round sizes track almost identically with team-led companies from priced seed through Series B. As Carta's head of insights put it, there's no "risk tax" once you're actually being evaluated. The resistance isn't in the terms, it's in whether you get taken seriously enough to sit at the table in the first place.

I used to believe this too. Find a co-founder from your old job, from university, from your circle, shared history, lower risk. The research doesn't line up neatly. Jason Greenberg and Ethan Mollick's 2025 Journal of Business Venturing study found teams with at least one stranger were more than twice as likely to fail as teams of friends, family, or co-workers, so pure familiarity does beat pure strangers. But the Outcast Ventures Billion-Dollar Founder Study, analyzing nearly 350 U.S. tech IPOs, found founders who'd worked together before saw 21% lower exit valuations, and university ties saw 7% lower. Wasserman's research found friendship specifically increases founder turnover by close to 29%.

The one category that held up as stable was former co-workers, tested under real work pressure, not social pressure. "Co-found with someone you know" is really hiding the actual variable: someone you've already been pressure-tested with.

Programs like Antler take the matching idea further: show up without an idea or a co-founder, get paired with strangers in weeks, pitch as a team by the end. But there's no independent study showing forced-matched teams outperform solo or self-selected teams, only the accelerator's own portfolio numbers, the same funding-versus-success gap again. Across nearly 1,800 portfolio companies and a decade of operating, public trackers put Antler's unicorn count at two to four. Not nothing, but not a validated formula.

None of this means you should try to know everything yourself.

I’m building SoPhy now, on my own, I lean harder on trusted advisors than I ever did on any co-founder. An advisor gives you their read on a gap in your knowledge and lets you make the call. A co-founder has equal authority to make that call for you, whether you agree or not, and then you're negotiating instead of deciding.

None of this means co-founders are a mistake, plenty of companies are built well by people who found the right partner and had the hard conversations early. What I'd push back on is the assumption in almost every piece of startup advice, that going alone is the risky, unproven choice and going with a co-founder is the safe, validated one. The data doesn't support that hierarchy.

Solo, you carry every decision and blind spot yourself. With a co-founder, you're betting two people's convictions stay aligned through years of a business, and their own lives, changing shape under them. I watched that bet fail five times before I considered the bet itself was the problem, not my ability to pick a partner.

I can't tell you going solo was the right call for Rare Founders. I can tell you it's the first time I built something on my own judgment instead of borrowed conviction, and three years in, it's a brand people in this industry actually trust. That's not proof. It's the most honest data point I have.

If you've got genuine conviction and you're building solo because it's right for you, not because you couldn't find the right person yet, that's not a red flag. It's a legitimate way to build a company.

It took me five attempts at the other version to believe that.

✅ Know a founder quietly doubting themselves because they're building alone? Send them this. The sooner more of us admit that going solo is a legitimate call, not a compromise, the sooner we stop mistaking borrowed confidence for conviction.

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