A16Z’s verticalization was driven by a principle from legendary investor Dave Swenson: an investing team shouldn't exceed five people. This small size ensures that investment discussions remain true conversations, preventing them from becoming unwieldy presentations and preserving decision quality as the firm scales.

To maintain agility and deep expertise at scale, Andreessen Horowitz restructured into independent, specialized teams for sectors like bio, crypto, and AI. Each sub-team operates like the original firm, preventing large, unproductive group decisions and enabling focused expertise.

In fields like finance, communities with strong internal communication and vested interests make better long-term decisions than purely quantitative models. The group's "shared wisdom" provides a broader, more contextual view of risks and opportunities that myopic mathematical approaches often miss.

The firm avoids the pitfalls of scale by organizing into small, autonomous investment groups (e.g., crypto, infra). This design, inspired by early Hewlett-Packard, provides the speed of a small team with the power of a large institution's brand and capital.

Unlike committees, where partners might "sell" each other on a deal, a single decision-maker model tests true conviction. If a General Partner proceeds with an investment despite negative feedback from the partnership, it demonstrates their unwavering belief, leading to more intellectually honest decisions.

Horowitz's steelman argument for small VC firms is that most firm structures are incompatible with scale. Partnerships with shared control can't make the hard decisions needed to reorganize. Furthermore, a single investment committee with 20 people destroys the candid, truth-seeking conversation essential for good investing.

The concept of Dunbar's Number, which posits a cognitive limit of about 150 stable social relationships, is not just theoretical. Companies actively use this principle to cap the size of working groups and even entire facilities to keep communication efficient and prevent the growth of stifling bureaucracy.

To maintain agility while scaling, A16Z models itself after the original Hewlett-Packard, operating as a series of small, autonomous groups (e.g., crypto, infra). This structure blends the power and resources of a large organization with the speed and ownership of a small one.

To combat communication breakdown at scale, Capital Group deliberately disaggregated its equity team into three distinct, firewalled units of about 100 professionals each. This ensures investment discussions remain intimate and effective despite massive firm-wide AUM, forcing them to "stay small."