They've slogged through years of belt-tightening and downsizing, and endured endless requests to work harder, smarter or just plain longer.
Now, experts say signs of life in the job market could start pushing some employees to do what they've been dreaming about, perhaps for years: quit. Too bad their employers probably won't see it coming.
"Most companies are probably not fully prepared for all the … pent up turnover that is likely to come when the job market really turns around," said David G. Allen, a management professor at the University of Memphis who has studied employee turnover extensively.
Experts say employers appear to have grown pretty complacent about whether their employees will find a better job somewhere else. And even as many bosses have complained about how hard it is to find good workers, few have paid much attention to keeping the ones they have.
"People are saying that they can't find the right talent, and yet when they do, they don't take such good care of it," said Sandi Edwards, senior vice president of AMA Enterprise, an arm of the American Management Association that helps companies improve their workforce.
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For the most part, employers haven't had to work too hard recently to keep good workers. The unemployment rate hit a high of 10 percent in the fall of 2009, just as the nation was officially coming out of recession, and it has remained elevated even as the economy has slowly added jobs.
The jobless rate stood at 7.7 percent in February, with 12 million Americans actively looking for work. The March unemployment report is scheduled to be released Friday.
That's left many workers grateful just to have a job, and finding that few new jobs were available if they didn't like their current one. The job market is improving, but Allen cautions that it isn't strong enough yet for employees to really have the upper hand.
There were 3.69 million job openings in January, according to government data, up from about 3.42 million in January of 2012. About 4.25 million people were hired in January, up from 4.12 million a year earlier.
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But in some fields, experts say they are starting to see workers leave for better offers.
Paul McDonald, senior executive director of staffing firm Robert Half International, said employers are already seeing it in areas such as specialized accounting.
"If there are employers around and they haven't experienced staff leaving them yet, they will shortly," he predicted.
McDonald said some employers may be aware that the risk of losing their best employees is on the horizon, but they aren't necessarily taking the right steps to stop it.
A recent Robert Half survey of 2,100 chief financial officers found that 38 percent said retaining valuable staff was a top concern for the next year, but only 13 percent said improving morale and engagement was a top concern. He thinks it's a mistake not to be working harder to make employees happy.
"The main reason people leave is unhappiness with management," McDonald said.
It's not necessarily a bad thing for some unhappy employees to quit. Peter Hom, a management professor at Arizona State University, noted that workers who are just there because they can't find a better job aren't usually the best ones, anyway.
"They don't perform as well or they don't engage in a lot of things that fall outside of their job description," he said.
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Still, Allen notes that that the first employees to quit when the job market improves are usually the ones you least want to lose. That's because a company's most valuable employees are often the most sought after.
Many researchers argue that it's not just money that keeps workers loyal, although a nice pay package and good benefits certainly help. But Allen said his research has shown that workers also place tremendous importance on relationships with other colleagues, and especially bosses.
"I think smart companies need to make sure that they're making their employees feel valued," Allen said. "If they're asking more from them, then they have to give more, in some way. It doesn't necessarily have to be money."