I think it comes down to management recognizing issues within their staff and working to address them through training or correction.

Many people don't like the idea, but metrics are a way to improve it.

If person X closes 150 tickets per month and person Y closes 10, it gives management something to work from other than an anecdotal feeling or a group consensus. I understand (all too well) that not all tickets are created equal, so my oversimplification needs to harness some other value matrix that makes sense for your company.

Deriving continuous improvement through measurement is the "next step" in the capability maturity model that many/most places never reach.

~Craig