I'm not sure I'm convinced that overqualified candidates either higher maintenance or more likely to quit. That hasn't been been my experience and I know my experience is limited, the HBR article cited however seems to back up my personal experience for what that is worth.
The variables around why someone works somewhere and whether or not they quit has, again in my experience, been more very strongly correlated with how well they like their job. And it is the factors that they "like" or "dislike" about there job rarely relate to how experienced they are or are not, and are much more likely to be based on whether or not they feel they are respected for their work, if they like or dislike their peers, like or dislike the day to day of their job, and like or dislike their office configuration (environment). That is the basis for my belief if "over qualified" is the single factor left over then it doesn't seem to correlate how successful they will be in the job.
All that said, and specifically addressing the analogy, the things that I find make for 'high maintenance' employees are an inability to hear constructive criticism (so poor self awareness), a lack of curiosity (so unable to see the questions that need to be asked), and a lack of respect for their work (so they aren't really trying to improve at all).
Does that make them Ferraris or Jaguars ? :-) Sometimes the more expensive car (like the Model S) has a lower total cost of ownership, sometimes it doesn't. But it has been really interesting thinking about the "maintenance" cost of employees from that perspective.
"Now, here's where it gets interesting: if you figure that all cars depreciate, and you drop the $8,500, I only spent $4,629.81 for the year. And if you get really crazy, and you take out "unusual" repair items — namely the tires, brakes, and battery, which will last several years without another replacement — my total cost was limited to two oil changes and a tire patch – or approximately $835.75. Not so bad for a year with a Ferrari."
Initially, it will seem like a great deal to get a Ferrari for the cheap price, but if you actually intend to use it, there are very practical reasons why it will cause a lot more problems simply having it, than having a Miata. If you can't afford to use the Ferrari properly, it will end up costing you more.
In the same vein, hiring an overqualified candidate WILL cost you more money and opportunity because they will leave quickly, and you could have spent the time training a more properly qualified candidate. I've been in the business 25+ years and I've seen this mistake time and time again. Maybe soon I'll be the one who is overqualified as well, who knows, but it is a legitimate reason to not hire someone.