Earlier quoted context omitted.
Last I checked, nearly everyone in tech hops jobs frequently. In fact that’s common advice for comp advancement. In my personal experience that advice holds true, even though I change jobs much less frequently than most of my peers (which means my comp tends to lag behind theirs).
I've refused to hire people who job-hopped every year or two. With a record like that, there's zero reason to expect they're going to stick around. Why invest in bringing them up to speed if they're just going to leave?
Frankly speaking you really shouldn't be hiring anyone with the expectation that they'll be in their role more than a year or two. Ideally, you're working with them to move into a position with more responsibility and then you need to backfill their position anyway. What does it matter if their next role is with you or somewhere else?
It's a lot to ask for every company to have a role available for every employee when they're ready for more responsibility, and expecting them to just hang around waiting for their chance is pretty naive, I think.