ACROSS cultures and industries, managers strongly prize “cultural fit” — the idea that the best employees are like-minded. One recent survey found that more than 80 percent of employers worldwide named cultural fit as a top hiring priority.

When done carefully, selecting new workers this way can make organizations more productive and profitable. But cultural fit has morphed into a far more nebulous and potentially dangerous concept. It has shifted from systematic analysis of who will thrive in a given workplace to snap judgments by managers about who they’d rather hang out with. In the process, fit has become a catchall used to justify hiring people who are similar to decision makers and rejecting people who are not.

The concept of fit first gained traction in the 1980s. The original idea was that if companies hired individuals whose personalities and values — and not just their skills — meshed with an organization’s strategy, workers would feel more attached to their jobs, work harder and stay longer. For Southwest Airlines, screening job candidates based on their willingness to provide a wacky experience for strangers contributed to the fun environment that enabled the company’s financial success. Likewise, for the investment firm Bridgewater Associates, which seeks to distinguish itself through its pursuit of transparency and honesty, screening out potential hires who couldn’t handle criticism made good business sense.

But in many organizations, fit has gone rogue. I saw this firsthand while researching the hiring practices of the country’s top investment banks, management consultancies and law firms. I interviewed 120 decision makers and spent nine months observing the recruiting practices of one firm in particular. The professionals I spoke with, who were charged with reviewing applications and conducting interviews, consistently underscored the importance of cultural fit in hiring. While résumés (and connections) influenced which applicants made it into the interview room, interviewers’ perceptions of fit strongly shaped who walked out with job offers.