How should the measurements change if the customer’s requirements change over time?
If you pay bonuses internally for good work, shouldn’t you do the same externally?
That is not the tone you want to set when you are entrusting your business processing to an outside company.
How has the provider managed their business and technology investments in ways that benefit you?
The primary goal of creating SLAs should be to create metrics that mean something to your organization.
What you want are metrics that will improve the service and provide impact not only to the bottom line but to the end user or customer.
The outsourcer has a responsibility to deliver a quality product and they should be viewed as an integral part of the overall corporate organization.
Since they are not an actual part of the organization (may be aligned on processing but not on your ultimate business goals) they need to be monitored in a co-ownership manner to ensure that the objectives of the outsourcing process and the terms of contract are being met.