I don't see how that is relevant, but let's consider someone further down the chain.
"Ah yes, Jimmy Postdoc, I see you have published 3 papers with an average impact factor of 3.1. Have a promotion."
vs
"Ah yes, Jimmy Postdoc, I see that you're making progress in improving quantum error correction, as evidenced by the fact that we can now use 80% of the previously required qubits to complete Shor's factoring assuming a surface code - great work, you should get that paper out at some point but keep focused on the work for now.
I'm also really pleased with your contribution to the academic community in the dept, particularly helping out Polly PhD student with her SAT formulation of decoding. The constructive questions in her talk really opened up a new line of enquiry. Great job.
Given all the above, have a promotion."
Metrics are stupid, people are smart, stop using stupid.
The subjective valuation lead to quite a lot of nepotism and unfairness. There is techno-babble you can use to pick pretty much anyone if you are good enough with words.
I agree that's a problem of traditional management. The way to counter it is good management methods, in particular ensuring that reviews and promotions are cross-validated using other personnel, both horizontally and vertically. I'm sure you're right though, some bias will slip through.
The question you have to ask yourself is whether you are prepared to tolerate occasional suboptimal decisions for a metrics based evaluation that _corrupts the entire system_.
"Ah yes, Jimmy Postdoc, I see you have published 3 papers with an average impact factor of 3.1. Have a promotion."
vs
"Ah yes, Jimmy Postdoc, I see that you're making progress in improving quantum error correction, as evidenced by the fact that we can now use 80% of the previously required qubits to complete Shor's factoring assuming a surface code - great work, you should get that paper out at some point but keep focused on the work for now.
I'm also really pleased with your contribution to the academic community in the dept, particularly helping out Polly PhD student with her SAT formulation of decoding. The constructive questions in her talk really opened up a new line of enquiry. Great job.
Given all the above, have a promotion."
Metrics are stupid, people are smart, stop using stupid.