[bowenjin]

The problem with raises and promotions is that it's slow, requires a lot more work from the manager, and doesn't increase the manager's number of reports. Thus hiring externally is a lot easier and more beneficial to the manager. Especially for those managers who are serial job hoppers themselves.

Another factor is the recruiting teams are assessed on conversion, how many passed phone screens, on sites, and offer accepts etc, but not on the performance of those employees after they join. So recruiters just spam anyone they think will have a remote chance of passing some stage of the interview process.

There have to be consequences to hiring a bad hire for the recruiting team and they have to be severe enough to make recruiting risk averse.

But this will never be the case if the organization is in growth mode where everything manager is trying to get as much headcount and hiring as fast as possible.