The purpose of SLA’s in IT Operations is to ensure a certain level of service to your business user community. It is typically used in outsourcing contracts to ensure the outsourcing partner reacts promptly to an issue raised, and ideally you also want to have an agreement on the maximum time until an issue is resolved. So in short the SLA-clock is ticking as soon as a ticket is raised.
The resolution time is a challenging one, especially in situations where your outsourcing partner perceives that they are not in full control over the value chain to deliver the outcome.
Assume that we have a functional service degradation issue that impacts all users, some feature in a solution does not work anymore and we need to go do root cause analysis on where things go wrong in the complex solution stack. Typically such situations are caused by a configuration change somewhere, and it is not rare that your subcontractor needs to do a level 4 ticket escalation to the vendor of the solution. Afterall you have a support contract with that vendor for that right?
However, did you know that many outsourcing partners explicitly make their own SLA-clock stop as soon as they raised a ticket with the vendor? For sure a smart way to avoid SLA-penalties for them, yet how does that serve you as an end-customer?