Ever been at a job that’s just a really, truly bad fit? Or had a bait-and-switch situation where you think you’re being hired for one job, and be assigned a totally different job when you come to work? Or started a job, only to have a round of  layoffs hit you quickly?

These are just a few of the examples that come up on the multitude of job advice websites as reasons why you might choose to not stay at a job for very long. What exactly counts as “not very long” is a whole different question, however. Fortune Magazine suggests that anything less than 18 months is just not socially acceptable. Monster.com writes that anything less than a year is considered a “sudden departure.”

The one thing that most of the advice seems to agree on one thing — that a short tenure at one job isn’t a terrible thing if you have a good reason for leaving. It’s when you have repeated short tenure jobs without a good reason, then it’s a red flag for those who are hiring.

Then again, a “short” tenure at a job has a changing definition. According to the US Bureau of Labor Statistics in September of 2016 (the most recent date they researched this question), average tenure at a job is 4.2 years, which is down from 4.6 years just two years before that.

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