I can't tell you what that little ingredient is which makes that first person want to go on and aggressively do more, and the other person be content to not do that. It's a mystery, but it does happen. ↗
It is not as though the process of production holds any mystery for me, I know exactly what it involves and I know the predominant concern in shooting one of those things is production values - or as they would say, seeing it all up there on screen. ↗