Brian Nichols is the co-founder of Angel Squad, a community where you’ll learn how to angel invest and get a chance to invest as little as $1k into Hustle Fund's top performing early-stage startups

Every investor has a secret sauce. A lens through which they view startups and decide where to place their bets. This is their investment thesis: a hypothesis about what makes a startup likely to succeed.

Without a thesis, you are just reacting to whatever pitch deck lands in your inbox. With one, you have a filter. A way to evaluate opportunities consistently and get better over time.

Here is how Eric Bahn, co-founder and GP at Hustle Fund, built his thesis, and how you can start building yours.

Eric's Thesis: Hustle (But Not the Way You Think)

When you hear "hustle," you might think of Gary Vaynerchuk-style grind culture or late-night coding sessions fueled by ramen and RedBull. For Eric, it means something more specific.

Eric defines hustle as great execution meets high velocity. It boils down to three things: exceptional productivity, rapid learning, and relentless focus on metrics.

This trifecta forms the cornerstone of his investing approach. And it is why the fund is called Hustle Fund in the first place.

Exceptional productivity means doing more with less. In the early stages of a startup, resources are scarce. The ability to ship fast, test fast, and iterate fast is a massive differentiator. The founders who can accomplish in two weeks what others take two months to do have a structural advantage.

Rapid learning means the hypotheses that founders have in the early days are often wrong. That is expected. What matters is how quickly they absorb new information and adapt their strategy. Teams that learn slowly die slowly.

Relentless focus on metrics means identifying the most impactful numbers and getting laser-focused on moving them. Great founders experiment rapidly and measure everything. They do not just track revenue. They understand exactly which levers drive it.

The Origin Story Behind the Thesis

Every investor's thesis traces back to some formative experience. For Elizabeth Yin, it was the pain of customer acquisition at her startup LaunchBit. For Eric, it was working at Facebook.

At Facebook, Eric worked alongside engineering and product teams that were absolutely crushing it. They wrote code 10x faster than other teams. They shipped features 10x faster. They learned 10x more. These super producers were not all Ivy League grads with PhDs. Some had only a high school education. Yet they were outperforming teams with elite credentials.

That was the lightbulb moment. It shattered the conventional wisdom about what makes a high-performing team and shaped how Eric evaluates founders to this day.

How Eric Measures Hustle in the Wild

Here is where it gets practical. Measuring hustle is a lot less straightforward than measuring revenue or customer satisfaction. A pitch deck can only tell you so much. So Eric looks for specific behaviors.

Founders who build in public. Sharing progress, failures, and learnings openly signals confidence and transparency. It also shows they are moving fast enough to have things worth sharing.

Founders who offer radical transparency. Honest, detailed investor updates. Not the kind that sugarcoat everything, but the kind that lay out what is working, what is not, and what the plan is to fix it.

Founders who prioritize experimentation and measurement. Constantly testing hypotheses and staying focused on key metrics, even as those metrics change over time. The Webflow founders are a great example. Eric invested in the earliest days because of how they thought about customer acquisition. They picked a specific persona (independent web designers), built an email list of hundreds of thousands, warmed that audience with newsletters, and then converted them into customers. That is hustle in action.

Rupa Health is another example. Founder Tara Viswanathan was one of the most measurement-oriented founders Eric had ever seen. She was not just tracking revenue and burn. She was tracking nuances like what caused clients to churn, how to identify and activate excited clients into advocates, and how to spot early warning signs in orders that indicated a client was struggling with the platform.

Building Your Own Thesis

You do not need to copy Eric's thesis. In fact, you should not. The best thesis is one grounded in your own experience and pattern recognition.

Start by asking yourself: what do I know better than most people? If you spent 15 years in healthcare, you probably have strong instincts about which health-tech companies will find customers and which will not. If you built and sold an e-commerce business, you understand unit economics and customer acquisition in ways that most investors do not.

Your thesis should be specific enough to be useful as a filter, but flexible enough to evolve as you learn. Eric's thesis has not changed at its core (hustle still matters), but how he measures it has gotten more refined over hundreds of investments.

At Hustle Fund, every GP has their own lens. Elizabeth Yin emphasizes customer acquisition economics. Eric prioritizes velocity and execution. Shiyan Koh brings her own perspective. These complementary theses are part of what makes the evaluation process robust.

If you want to develop your thesis alongside a community of 2,500+ investors who are all refining their own approaches, Angel Squad provides the deal flow and frameworks to accelerate that process. Check it out at Angel Squad.

The best thesis is one you can actually use. Start with what you know. Invest. Learn. Refine. Repeat.