Plenty of quantitative research exists about both the rise and the effects of outsider executives.

For example, a recent paper out of the Wharton School shows that less than a third of top executives at Fortune 100 companies started their careers with the organizations they lead. Meanwhile, other research shows that previous experience as a CEO might be negligible in assessing leadership ability, and that there is little evidence of a performance discrepancy between internally-promoted leaders and those brought on from the outside.

But there isn't a lot of consideration as to why more and more executives roam from company to company in today's business world. Doing so requires a bit more of a qualitative, philosophical approach. Such an approach was recently applied in an interview with Gianpiero Petriglieri for Harvard Business ReviewPetriglieri is an organizational behavior professor at global business school INSEAD.

Career Conflict

In the interview, Petriglieri refers to "Generation Flux"-- loosely defined as a generation of young business leaders who find work very important but express that by chasing their ambitions from organization to organization.

These nomadic executives, he says, were largely born of the economic crisis. These leaders "no longer having the prospect of stable, long-term employment or career ladders to climb," he says, so they "have actually been able to craft work lives that are more authentic, more expressive of who they really are, and also freer, less tethered to the demands of impersonal, instrumental organization."

That contemporary depiction, Petriglieri notes, is a positive one. The opposite perspective has historically been more popular: That leaders should be judged on their level of loyalty and years of immersion in their organizations.

"Most of us follow leaders not because of their resume or their skills or their job title," Petriglieri says. "We follow leaders because we trust them. And we trust them because we feel that they are one of us--that they understand what we want and what we worry about. That they have a vision for how we can get to where we want to go and steer clear of what we are afraid of."

The rise of Generation Flux speaks to a conflict between career aspirations and company needs, Petriglieri suggests. "The double bind is the following--while becoming a leader may require you to demonstrate flexibility and mobility and all that, being a leader requires you to demonstrate commitment. And flexibility and commitment are relatively strange bedfellows."

Petriglieri doesn't say that nomads can't effectively lead. But he does say it puts the burden on them to build relationships and build up the levels of trust and familiarity required of a leader at their companies.

"It's only bleak if you try to be a leader, rather than someone's leader or the leader of a group or an organization or a cause," he says. "Then you end up being no one's leader."