The days of joining a company straight out of school then spending your entire career working your way up have largely ended. Whereas there were once stigmas associated with job hoppers -- people who traded jobs frequently -- most American workers don't think that way anymore.

A full quarter of workers in sales, office, and management/professional occupations (25.7%) said they are actively seeking new job opportunities while another 55.5% answered that they were "passively open to new job opportunities," according to a new survey of 1,000 full-time workers commissioned by Accounting Principals and Ajilon.

A person is using a laptop to search for a job.

Most of those surveyed think that one or two years is long enough at a job where it's OK to start looking. Image source: Getty Images.

How long is long enough?

It's worth noting that it's not just restless employees or people hoping to get a little more money or a promotion that have changed the idea of how jobs work. Workers often don't stay at a company and work their way up because some employers no longer offer the loyalty that was once mutually expected.

Workers quit for new opportunities and employers lay people off when it makes sense for them. That creates a sort of mercenary world where both workers and employers look out for their own interests first.

Over half (59%) of all respondents felt that one to two years is long enough to stay at a job before looking for a new one. About 15% of those who were surveyed said that you should always be looking for new opportunities. That makes sense because today's average worker will hold 10 jobs before they turn 40, according to Bureau of Labor Statistics data cited in this Motley Fool article.

"With the unemployment rate hitting record lows, the labor market is tighter than ever," said Accounting Principals and Ajilon President David Alexander in a press release. "Employees are more receptive to considering inbound job opportunities and the cultural norm for an acceptable length of time to stay at a company has shifted."

What can entice people to stay?

Having a positive, supportive office environment can help keep employees from jumping ship. Over half of those surveyed (53.6%) cited loyalty to their boss, coworkers, or company as the top reason they don't leave. Conversely about one-third (32.5%) named "a bad manager or boss" as a top reason to leave, behind only "being underpaid" (34.8%).

"Loyalty is a big factor for why employees stay at a job," said Alexander. "Workers who feel connected to their teams and company mission are more likely to be engaged and seek out growth opportunities, while those who feel they are suffering under inadequate managers are likely to look elsewhere."

What should you do?

It's always smart to be open to opportunity. You may like or even love your job, but if the right offer came through it would be silly not to at least hear the details.

Before actively looking, however, it's important to know what you really want. Are you leaving a good situation due to a fixable problem? Are you being petty or short-sighted?

If the answers to those questions make it clear that leaving is the right choice, do so the right way. Conduct a quiet, professional search and when you find what you're looking for, give proper notice, and do everything you can to leave in a professional fashion.

Just because having a new job every year or two no longer carries a stigma doesn't mean there's any shame in staying in one place. Switch jobs when it makes sense for you and make sure that where you're going is truly better than where you are.