ZUNZUNSTARTUPS
Recently, I had the chance to catch up with an early-stage startup founder. He shared, in a calm and positive tone, that his co-founder had left the company—he was now a solo founder. This change allowed him to move faster. With full autonomy, he could make decisions on his own and execute more quickly. I listened carefully. After reflecting for a while, I shared with him that everything has two sides. Being a solo founder can indeed enable faster decision-making and execution. But when it comes to going far and going long, the equation becomes more complex. Why is that? I would like to share a few reflections through this blog post.
People often describe entrepreneurship as a journey of opportunity, creativity, and breakthroughs. From my perspective, however, it is equally a journey filled with continuous challenges and risks, which may stem from strategy, product, finance, people, and quite often, from the founder’s own ego. In that journey, a co-founder—if it is the right person—is not merely someone who shares the workload or the vision. A co-founder can be one of the most natural and effective risk-control mechanisms a startup can have. This person is not there to slow you down or hold you back. Rather, they help ensure that critical decisions are not swept away by overconfidence. I have observed that many major startup failures do not arise from a lack of capability, but from the absence of someone close enough, honest enough, and strong enough to say a seemingly simple sentence: “Wait a moment—let’s think this through again.” Without a strong counterbalance, founders can easily fall into a dangerous loop: confidence leads to faster decisions, fewer explanations, less accountability—and then greater confidence. In those moments, a co-founder serves as a true mirror—reflecting the blind spots we cannot see and keeping the ship from drifting too far off course.
I have also heard many stories of solo founders who gradually turned their startups into what I would call a “limited liability company of oneself”—even though legally the company is a joint-stock entity with multiple shareholders. All major and minor decisions revolve around one person. When the solo-founder state persists without alternative governance mechanisms, hidden costs begin to accumulate. There is the cost of carrying all strategic decisions alone, which may result in becoming either overly cautious or excessively bold. There is the cost of intellectual isolation, where the absence of peer-level debate dulls critical thinking. There is the bottleneck cost, where every key decision requires approval from a single individual, reducing accountability and transparency, and eventually creating governance risks that hinder long-term growth. These costs rarely appear in the first year. But after several years—when the company grows larger and complexity increases—they become much more visible.
I deeply empathize with solo founders. Finding the right co-founder is far from easy. As I have shared in my blog post before, if you have not found the right person, it is better to move forward alone than to choose the wrong partner just to fill a seat. A solo founder can certainly grow a startup. However, going far and sustaining long-term growth requires a much higher level of discipline and self-awareness. A solo founder must consciously build the mechanisms that a co-founder would otherwise naturally provide: a board that truly dares to challenge, a strong core team capable of open debate, and a clear delegation structure to avoid carrying everything alone. Without someone at the same level to provide reflection, the solo founder must intentionally create that mirror and continuously practice self-awareness—reviewing decisions, reflecting on blind spots, and striving for personal growth.
I often say that choosing a co-founder is not addition—it is multiplication. Choosing the wrong person is like multiplying by a negative number: the result does not simply stagnate; it drags everything downward. Choosing the right person is like multiplying by a positive number: it does not merely multiply capabilities, but also multiplies the founder’s ability to grow and the startup’s potential for exponential growth. In the short term, being a solo founder may resemble addition—keeping the total positive and sometimes enabling faster movement compared to working with an incompatible partner. But in the long term, multiplication is what determines whether a startup can truly go far.
As an early-stage startup investor, what I hope to see in a startup looking for investment, is a strong founding team that embodies a multiplication mindset. If it is still too early to find the right co-founder, what I truly care about is whether the solo founder is actively building risk-control mechanisms, whether they allow sufficient challenge and counterargument, and whether they are preparing for multiplication in the future—through thoughtful, strong team-building and structural planning that enables exponential growth and long-term sustainability. I hope these reflections offer small but meaningful suggestions for founders who are wrestling with the challenge of choosing a co-founder. Yeah, let's keep fighting, founders!