Metrics - It's important

Metrics play an important aspect in every business. In the Support world, it is imperative that we measure performance in terms of specific numbers. If people don't understand the importance of driving numbers, then that's ok. You can explain as to how numbers convert into revenue and the well being of an organization. If you have someone who understands it, but refuses to work with them, that's an issue. Yes - Taking care of your employee is critical to every business, but if that employee does not want to work with numbers and mentions that we keep driving in terms of numbers, then you have to take a look at the employee and decide if you want to keep him or leave him.

In Tech Support world, there is only 1 metric - Customer Satisfaction.

What about the rest?

Well, the rest of the parameters / sub-metrics, influence the Customer Satisfaction scores. In the Support world, typical parameters to be look at are:
Initial Response time
Average Response time
Average Hold time (If it is voice based)
Longest Hold time (If it is voice based)
Productivity of an agent / Engineer (# of cases handled / resolved / closed/etc.)
Backlog (# of cases/tickets/incidents)
Backlog age (in days)
Average Resolution time,
etc....

These parameters play an important role in rolling up to the overall Customer experience/ Customer Satisfaction.

There is 1 other outside factor that I truly believe matters - Employee Engagement.
Happy Employees can easily be converted to Happy Customers as long as they are engaged in the business and they understand how critical their role is to the organization.