Ben Slater has a great post on service level agreements:
It should set the customer’s expectations, be realistic and be crystal clear, with no scope for misinterpretation. Well, that’s how they are meant be. But unfortunately, in the quest for more sales, some MSPs tend to commit themselves to unrealistic SLAs. It’s tempting to buy into a service when an MSP offers you 100% availability. It is even more tempting when you see a compensation clause that gives you confidence in going ahead with that MSP. But hold on! Have you checked out the exclusion clauses? Have you checked out your responsibilities in order to get what you are entitled to in the SLA? Just as it is the MSP’s responsibility to define a crystal-clear SLA, it is the customer’s responsibility to thoroughly understand the SLA and be aware of every clause in it. That is how you will notice the shades of gray!
We have put together a list of things to look for in an SLA so that customers are aware of the nuances involved and avoid unpleasant surprises after signing on.
This is important to know when you’re using a managed service but it also works internally: as a developer or manager on a product that people (presumably) rely upon, how you deal with outages and issues matters a lot.