On the other side, the company can create a nice "market" by tuning it correctly. When I was at Intel, it was relatively easy to get an internal hiring req, and relatively difficult to get an external one. And... the total number of internal hiring reqs was allowed to over-subscribe the total authorized head count. Coupled with a rule that no manager could block an internal transfer for more than a couple of weeks of clean-up, the net effect was that there was a certain amount of "hole flow", and you could always identify a bad manager by the vacuum that surrounded them. Overall, I thought that was brilliant.

As to people on re-deployment, it did happen that poor performers had a hard time landing a new role -- but then again, they would have had a hard time staying in the company in their old role, so that kind of fits your point. But Intel didn't use redeployment as a "shadow RIF". Intel was not shy about moving people out of the company -- they didn't need to nor bother to hide it.

Back to redeployment -- I can remember occasions of fairly large redeployments (business unit shutting down) where those of us in parts of the company considered more strategic would find ourselves suddenly rich in hiring reqs. Again, the company created the right market conditions and let the hiring managers and employees sort it out.

Unless their skillset just isn't needed at that location anymore and they can't move to a different city for example because they have children in school.

I guess it helps keeping the workforce young and flexible.

A vast majority of full time Googlers are bucketed onto ladders that are needed in pretty much any team. Say SWE, SRE-SWE (that can switch to SWE at will), TPGM, all kinds of managers. Much of the remainder are people who should be able to do the switch, say SRE-SWE to SWE, within the grace period. Legal and accounting might find themselves in a pickle, but these don't move often.

It'd be interesting to study. My intuition is that over the long term it'd cut in the opposite direction--smart people will move on while bottom tier will linger as long as possible.

Smart is the wrong word - more like savvy googlers usually have an internal network and know what teams are hot. They move on quickly.

Bottom tier can't linger long if they have 90 days to find a new job or get fired.

In my experience the best leave at the first redeployment. Each subsequent buyout the smarter ones leave, it's rarely the crap people that take a buyout or leave altogether.

I've heard this where the Big Head meme from Silicon Valley comes from.