The critical value driver of any business – any business – is [customer/user/client/subscriber] engagement.
This can manifest itself in different ways, for different types, at different times, with different frequencies, but the idea is principled and constant.
The feedback loop, the top of mind, the recurring interaction, are ways of describing the same concept, whether a Netflix subscription or behind the wheel of a Tesla vehicle.
The social and other networks are more obvious examples, almost embarrassing to even mention.
At the other extreme, if there is one single purchase of one single item, the value created by this event is virtually nil, notwithstanding the immediate revenue gratification.
I may have touched on this theme in this space before (though maybe not as bluntly), but was reminded about it in yesterday’s Fred Wilson post…

… and it isn’t repetitious, I don’t think, to bring it up again.