Robinhood had raised around $1 billion from venture capital firms such as Index Ventures and New Enterprise Associates, privately valuing the start-up at around $7.6 billion The company has become a Silicon Valley darling by presenting itself as a tech-savvy alternative to traditional stock trading platforms. But the first week of March 2020, with the financial markets in chaos, the start-up’s technology failed at the most crucial moment. On Monday and Tuesday, as global markets rebounded after a sell-off last week and then sank again, Robinhood’s trading platform went offline, leaving many customers to watch their portfolios drop in value without being able to do anything about them. Robinhood has attracted millions of millennials to trade on its platform, largely by eliminating trading fees and making stock trading as easy as ordering food online. This week, many of those same customers said they wanted to get their money out of Robinhood as quickly as possible.