> A good manager doesn't need PIPs because they're always communicating clearly and consistently to their reports about how they're doing.

I'm not sure this is true. I'm definitely open to the idea that I was a bad manager or there were things I wasn't doing well, but not communicating my expectations clearly is not something I've ever been accused of. Or at least not once I had some experience. Management comes with a learning curve.

I have had an employee where I and their direct manager were very much communicating they weren't meeting expectations, including coaching and providing warning that their job was now at risk, that only did a 180 when put on a PIP. I think for some people there is power in putting a concrete date on things vs something that needs fixed "soon".

The employee in question continued to improve post-PIP and got promoted. I don't know what happened after I left the company, but I have no reason to doubt they continued to do well.