What investors really think about the TAM slide in your pitch deck • TechCrunch

We’re encouraged to think of pitch meetings as a trial by fire: If an entrepreneur can negotiate deadly traps and slay the doubt monsters that bedevil tech investors, they’ll be rewarded with a golden SAFE note at the end of their quest.

Particularly for first-timers, the pitch has become an existential drama, which can lead to poor decisions like overlong slide decks, failing to prepare investors before a meeting, and fatally, exaggerating the size of the total addressable market (TAM) in which they hope to compete.

“With TAM, it is almost guaranteed you’re going to be wrong,” Aydin Senkut, the founder and managing partner of Felicis Ventures, said at TechCrunch Disrupt. “It’s either going to be too large or too small.”

Kara Nortman, a managing partner at Upfront Ventures, said the TAM numbers given in a pitch do not control whether she’s likely to invest. “I would say [it is] more important to be able to articulate how big something can become and to show that you have a thought process around TAM, if it’s early.”

According to Deena Shakir, a partner at Lux Capital, TAM, along with the associated metrics serviceable addressable market (SAM) and serviceable obtainable market (SOM), aren’t meant to be carved in stone. They’re simple planning tools that help founders show investors their company’s upside potential, while SOM and SAM help them offset risk.

“If we’re taking the meeting, we all sensibly think there’s something there that’s interesting enough to be potentially venture-bankable,” she said. “The way it’s calculated and the way the founder is thinking about it tells us not necessarily about the business or its future, but about how the founder thinks about company creation. And that’s much more important at the earliest stage.”

All three panelists said TAM, SAM and SOM numbers offer a window into a founder’s mindset, but they’re not determinative factors, since they already have a general understanding of the sectors in which founders hope to compete.