“Probability of job loss is strongly monotonically declining in tenure,” with job-loss probability falling from 15% for first-year private sector employees to 5.8% after twenty years [1].

(If you’ve ever had to do lay-offs, you know that it’s easier to lay off the new guy than someone with deep ties to the team.)

[1] https://www.princeton.edu/~ceps/workingpapers/171farber.pdf page 31, Figure 16