Otherwise it’s just marking them for future termination without telling them, which seems like a waste of everyone’s time.
I did not say they should never tell the employee. I think sometimes it's unnecessary.
Giving the employee a chance to rebut any performance problem assumptions would be an important part of this, and would also require they know.
In my 15+ years doing so, I’ve never heard or seen a situation in a reasonable organization where someone gets on a list like this (intentionally, as compared to their manager screwing up by not having a conversation with them before it is clearly a huge problem to everyone else) without knowing they are going to get on a list like this if they don’t improve.
I have heard it at many places that are flogging employees or using scare tactics to get every cent worth of value they can put or people before they burn out and get thrown on the rubbish bin.
If management thinks you're doing a bad job, it's not needed to make it known to the entire team - but you should know.