The founder realized he had product-market fit not from praise, but from anger. When the system went down, his few early customers were furious because they had come to rely on it, even in its imperfect state. This is a powerful, non-obvious signal of true customer dependency.

While you gain deep empathy for one user (yourself), you risk creating a product so tailored to your expert needs that it alienates the broader market. This "market of one" paradox can lead to building powerful but commercially unviable tools for a niche group of power users.

Many founders start companies simply because they want the title, not because they are obsessed with a mission. This is a critical mistake, as only a deep, personal passion for a problem can sustain a founder through the inevitable hardships of building a startup.

Prepared's founder faced 'no's' from customers, investors, and parents. He persisted not because he was trying to build a company, but because of a stubborn, personal passion to solve a problem—believing he could make things 'slightly better' even if he ultimately failed.

Instead of searching for a market to serve, founders should solve a problem they personally experience. This "bottom-up" approach guarantees product-market fit for at least one person—the founder—providing a solid foundation to build upon and avoiding the common failure of abstract, top-down market analysis.

Founders often perfect their product (the dam) without validating the underlying human motivation (the river). When the product fails, they tweak the product instead of questioning if they've built on a real, pre-existing customer need. Rivers must be found; they cannot be created.

Despite selling to eight law firms at its first conference, Filevine experienced a brutal eight-month period with virtually no new customers. This highlights that early traction can be misleading and founders must endure long periods of zero growth before finding a working GTM motion.

When you build a tool to solve your own problem, the worst-case scenario is that you have a custom solution that improves your life or work. This makes every project a success on some level, reframing the concept of failure and encouraging action.

After five or six failed B2C ideas, Browserless founder Joel Griffith found success only when he pivoted to solving a problem he experienced personally as an engineer. This deep domain expertise in a B2B niche was critical to building a product that resonated.