Dear O.T.: It’s interesting that you consider yourself “in line for” a promotion. The new executive in charge of your division may see things differently. “When I retained a search firm to look outside for candidates, it was sometimes because I had ‘inherited’ people who weren’t ideal for what I wanted to get done,” says Rose Spano Iannelli, who held a series of executive jobs before co-founding recruiting firm Spano Pratt. “With a new leader, internal candidates are often at a disadvantage.”

Not only that, but higher-ups at your company may see next year’s overhaul as calling for skills that in-house candidates don’t have, or at least haven’t proven. “Businesses that are changing fast often want to find someone who can show experience at executing the strategy they see for the future, rather than people who have excelled in the past, particularly if an outside hire can bring new revenue opportunities,” says Iannelli. “So even the best internal candidate is not always the best person for a new role.”

Ominous as that sounds, keep in mind that companies’ reasons for bringing in a recruiter usually go beyond searching for outside talent. Here are four of them:

Talent benchmarking. Even with promising candidates in-house, an outside search “can be a way of comparing internal talent with what’s available on the open market,” says Iannelli. “How do you know you have the best unless you look?” It doesn’t necessarily mean an outside candidate will get the job, in other words; only that hiring managers are curious about who’s out there.

Competitive intelligence. Without revealing anything proprietary, so-called passive candidates — that is, people already working, often for competitors — can be a valuable source of knowledge. Iannelli notes that meeting with these folks can “give the organization, and hiring managers, a clearer understanding of the marketplace in their industry.”

Sharpening the employment brand. “Meeting recruiters and external candidates is usually the equivalent of entertaining strangers,” says Iannelli. “Explaining your company’s culture to people who are unfamiliar with it is a helpful exercise, because it forces hiring managers to sharpen the message about why someone might want to work there.”

Answering outsiders’ questions about what success in a given role would look like, she adds, can help define the job by “creating measurable requirements that might otherwise be overlooked.” That may be especially true in the case of jobs that haven’t existed until now, like the new roles your company’s restructuring will create.

Refining the company’s mission. Iannelli has seen some clients use a search as “a professional development tool for hiring managers and search committees,” she says. “Revisiting and defining the company’s mission and core values every now and then is useful. It can provide confidence in management’s day-to-day decisions” — or cause some of those decisions to be re-examined in a different light.

None of this tells you, of course, whether you’ll get the promotion you’re hoping for. The only way to get a clue about that is to sit down with your boss and, without putting him on the spot, have a candid discussion about your future. If you don’t get the job you have your eye on, what does he see you doing instead (assuming, of course, that you’re willing to stay)? How do you fit into the restructured organization? This is doubtless not the last chance you’ll have to move up, so try to take the long view and focus on this as “an opportunity for professional development,” Iannelli suggests. Good luck.

Talkback: Have you ever been passed over for a promotion in favor of an outside hire? How did you respond? Leave a comment below.

Have a career question for Anne Fisher? Email askannie@fortune.com.