SNL's Lorne Michaels and other superbosses all display this counterintuitive trait

For most managers, talent retention is key to running the business.

How do you make sure that your top performers stick around forever?

Well, you don't. At least not if you're a superboss, or the rare breed of leader who thrives on making other people successful.

The term "superboss" was coined by Dartmouth business professor Sydney Finkelstein in his new book, "Superbosses." In the book, Finkelstein explains that superbosses - whose ranks include "Saturday Night Live" creator Lorne Michaels and Oracle cofounder and former CEO Larry Ellison - often spawn an entire new generation of talent within their industry.

The way they do that isn't by holding onto employees forever. Instead, they know when it's time to let go of someone stellar who's moving onto something else.

In fact, the way superbosses become successful themselves is by creating industry-wide networks of people who have worked for them so that they're always well-connected.

"Everyone tries to optimize on talent retention," Finkelstein told Business Insider, but if someone wants to leave, you can't hold them back.

That's why the subtitle of Finkelstein's book is "how exceptional leaders manage the flow of talent." Superbosses are as concerned with managing their best employees out as they are with getting top talent in.

Maintaining ties with former employees is important. "When employees leave, don't forget about them or, even worse, see them as traitors," Finkelstein writes. "Instead, be smart: Act like a concerned godparent and stay in touch with them."

Sometimes networking isn't enough for superbosses - many actively look for opportunities to do business with former employees.

Finkelstein cites the example of Michaels, who executive produced Tina Fey's "30 Rock" and "Late Night With Jimmy Fallon" after they worked for him on SNL.

"That partnership is a win-win," Finkelstein told Business Insider. The superboss earns a reputation for having brilliant proteges, and therefore other talented up-and-comers flock to them. Meanwhile, the protege receives help with their career.

"It sounds obvious," Finkelstein said, "but people don't do it."