Why the man behind $2.8 billion Slack says the best thing to happen would be a 'giant crash'

Since its official launch in February 2014, the business communications app Slack has raised $320 million in venture capital. It's now worth $2.8 billion, making it the fastest startup to reach a $2 billion valuation. A lot of Slack's value is derived from its exceptional product, which is drawing in tens of thousands of new users every week. In February, it was adding $1 million in annual recurring revenue every 11 days. But Slack is also the beneficiary of one of the warmest VC markets ever. I...