As 2019 comes to a close, we've been in a boom period, but what happens next?
The big picture: This question was partly answered when the first stampede of private unicorns hit the public market in the spring. The results were mixed — but mostly not good. (Uber, anyone?) And of course, WeWork didn't even make it to the Nasdaq bell-ringing, instead breaking down shortly after it filed its S-1.