A huge amount of management effort goes into being proactive so you don't even need to get to the point in the conversation where they voice wanting to leave. Or when they do, you've seen it coming, have plans in place and they move on with your blessing.
* Creating a culture where employees (and managers) feel valued and have autonomy.
* Ensuring employees are clear about where they are headed, giving them something to work towards.
* Proactively identifying and unblocking issues before they become crises, often across functions.
* Identifying areas of frustrations for teams and individuals.
That's just a small number of the things you'll be doing, and whilst scope varies massively by company size (though until you get to the large corp environment most of this is still covered up to the VP / CTO level), you'll be juggling it all alongside technical input, cross functional leadership responsibilities (VP may well be in the SLT if the company isn't huge), horizon scanning, constant process refinement.. The pillars of people, process and technology all need to be constantly considered..
Having done this repeatedly from IC all the way through Head, Director and VP level (and up to CTO), I can say that being a proactive problem solver is always required of a good manager / Director / VP.
Edit: Having read the actual article ;)
IC paths map this quite well too..
Tech Lead maps to manager, Staff maps to Director, Principal to VP