More likely, they were viewing the company based on its potential as a highly liquid market, ambitious as that might seem today. Consider that the parent company to both the NYSE and the Chicago Stock Exchange currently has a market cap of roughly $45 billion. Then again, that company operates 12 exchanges and marketplaces altogether, and it enjoyed more than $6 billion in revenue last year by transacting more than a $100 billion dollars in volume on a daily basis on the NYSE alone. Perhaps most important to them, Carta is now as well-positioned as any outfit to capture and cater to the growing number of privately held companies looking to provide more of their employees liquidity and to cash out early investors.

https://techcrunch.com/2019/05/06/carta-was-just-valued-at-1-7-billion-by-andreessen-horowitz-in-a-deal-some-see-as-rich/?yptr=yahoo