I recently changed jobs, and this caused me to reflect on the motivations for changing companies. For engineers, and I suspect for many people, the easier it is to leave a job, the easier it is to stay. If your skills are staying up to date and marketable, and you’re comfortable that you could find another job if you needed to, then there is little risk staying where you are and seeing how it plays out. Even if there was a layoff with no warning, you could find another job.
If your skills aren’t staying up to date and marketable, then you start to worry about how you would bounce back if something unexpected did happen. This leads to listening to recruiters and looking around for a new position where your skills will stay marketable.
So if companies want to keep good employees around, the answer is somewhat counter-intuitive: you need to invest in actions which will make your people attractive to other companies, so that they don’t feel they have to leave while they still can.