Why is build "successful", but VR won't launch?

When I build for Windows 64 I get no red errors in output log, says successful at the end, but when I go to launch the game, SteamVR has everything green and Ready, I see on my monitor the camera is born at the floor, but in the HMD isn’t displaying at all, though I hear audio. HMD in SteamVR still shows solid green, but isn’t communicating it’s position on my desk to the game, and neither is the game sending video to the HMD. Many thanks for pointers!

I’m embarrassed! Big thanks.

I’m embarrassed! Big thanks.

You probably don’t have “Start in VR” enabled in the project settings.