The guy thinks that hiring a team of rocket scientists means that he is a rocket scientist himself and that it means that he already knows all there is to know about everything.
Never mind the fact that in the early days of SpaceX, there were people hired whose entire job was to distract Musk with bullshit work so everyone else that actually knew what the fuck they were doing could work around him.
I admit I don't have a direct source for this one. You spend a lot of time reading things and learning things, it's not really practical to bookmark every last thing you read or hear.