After a big vacation with family. Near a milestone birthday. Following a class or family reunion. New research looks at why more human resources departments should time career discussions to employees' personal life events, rather than professional ones. (iStock)

A disappointing performance review. An acquisition by some big faceless corporation. A bonus that was kind of 'meh.'

These might seem like the most obvious milestones that would prompt someone's job search activity -- fueled by feeling undervalued, under-appreciated or apprehensive about the professional changes to come -- to see a big boost.

But newly released research from the advisory firm CEB, highlighted in the newest issue of the Harvard Business Review, shows that such career-related events aren't always the biggest things driving people's decisions to jump ship. Rather, it's often more personal milestones, such as birthdays or class reunions, that cause people to rethink their work life.

In surveys of 8,500 employees, which asked people separately about both their job hunting activity and a variety of events that may have happened in the past couple of months -- ranging from getting a new boss to having a child -- CEB found that people tend to think about their careers in relative terms.

"What we came to realize is that when people think about whether they’re having a good career, they're thinking about whether they are they having a good career relative to other people, or relative to what their own expectations were" for their lives at a given age, said Brian Kropp, who runs CEB's human resources practice. 

Unsurprisingly, job search activity jumped the most, by 17 percent, when people had a change in their manager or their responsibilities. But just behind that was attending a major gathering with friends, family or classmates, such as a class reunion. And birthdays came in third, at 12 percent. More traditional professional moments that might prompt self-reflection -- an anniversary at the company, say -- sparked a 6 percent boost in job-seeking activity. And after bonuses are handed out or performance reviews are given, respondents' search for new employment actually declined.

Conceptually, CEB's data may not be all that surprising. That we continue to measure our progress by others' -- yes, even our arch rivals from high school -- or by where we thought we'd be in life by a major birthday, will make sense to anyone who's been to a class reunion or turned 40 years old. What's important about their finding is that it's not how most managers and organizations think about retaining their best people.

"Most [human resources] executives say we want to talk about careers during performance reviews and at mid-year," Kropp said in an interview. "But most people's lives don't conveniently follow the H.R. calendar."

In other words, companies ignore the personal and put too much focus on the professional. A few companies, Kropp said, are starting to get this, prompting their H.R. software systems to remind managers about certain personal milestones that might prompt self-reflection by employees about their careers, and urge managers to schedule career discussions around these times.

His advice for managers, especially as the labor market grows stronger and more people get in a position to voluntarily switch jobs: Pay more attention to personal milestones, not professional ones. "Know your employee's birthday, and about a month before have a conversation with them about their career," he said. Before they take an extended vacation, sit down and have a chat with them about opportunities.

Doing so -- in those moments when people actually stop to think about their lives and their goals -- could have them thinking they have an interested boss, rather than resolving to brush up their resumes as soon as they get home.

"You're sitting on the beach, having an adult beverage, going 'what am I doing with my life?' " Kropp said. "That's when decisions really get made."

Read also:

This big change was supposed to make performance reviews better. Could it be making them worse?

Why this Wharton wunderkind wants to replace intuition with evidence

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