Scott Amenta, who is, unsurprisingly, himself a chief of staff at Spring, has weighed in on the question in a detailed Medium post. Though he covers a lot of ground, here’s the one reason why the chief of staff is important at a unicorn.

Time Matters at a Unicorn

Growth is tricky to pull off: 70 percent of failed startups failed due to premature scaling. In a high-growth environment, time is a “critical asset.” As Amenta says: The chief of staff plugs the leaks that might overwhelm the company as it scales up, but which are easily missed by other teammates. Not even the CEO can do that job.

CEOs Never Have the Time

Amenta again: The chief of staff can handle the details while keeping up with the CEO’s bigger picture. And, if you’re among the NY-based CoS crowd, you’re in luck: Amenta’s looking to build a support group and you can contact him at scott@scottamenta.com to join his “not-so-secretive group of Chief of Staffs.”