ITIL 4 practitioners will have to understand two terms they will frequently encounter both in training and in the real world: utility and warranty. First, we'll define each term and then compare and contrast them.

Utility refers to the functionality offered by a particular product or service to meet a particular need. Basically, it's what a product or service does. It simply means that the product or service fits its intended purpose. Warranty is the assurance that the product or service will meet the agreed upon requirements. It's how a product or service performs. Warranty is concerned with the product's or service's ability to accomplish what it needs to do and is commonly referred to as fit for use.

A car would be a good example to use to then compare and contrast utility and warranty. As a consumer, you have a requirement to drive a car from point A to point B. You want it to get at least 35 miles per gallon of fuel efficiency and you live somewhere that gets really hot in the summer and really cold in the winter, so you want a good, cold air conditioning system and a really nice, warm heater. Now since we defined utility as being fit for intended purpose. Having a spouse and two small kids, a four-door sedan such as a Toyota Prius fits your purpose of getting your small family from point A to point B. And since you will be buying it brand new, it would certainly have high enough fuel efficiency and have a really nice air conditioner and heating system. This then fits into being fit for use which is what warranty is all about. So you buy the brand new Toyota Prius as it meets both your utility and warranty requirements.

But let's take it up a notch and say a few years go by and another child comes along the way. By now, you could picture out the small Prius being too small for the entire family to go around. It no longer is going to be fit for purpose because any time you want to go out to dinner as a family, you're now going to have to take two cars because you all can't fit into one little Prius. While the warranty might still be there because the air conditioner still works and the heater still works and it still gets over 35 miles per gallon, the intended purpose of getting the entire family from point A to point B all in that one vehicle can no longer be accomplished.

Ultimately, one of the important things to remember is that you need both utility and warranty for a service to operate successfully. In the IT world, we often see people focus on the warranty and they simply forget about utility. If I have a service that runs on a wonderful cloud infrastructure that can handle millions of users simultaneously, that is warranty. Most IT professionals like warranty because it's easy to measure. If you require that a service has a defined and agreed upon condition and you meet those conditions, you have good warranty. Utility simply requires that a service support the performance of the consumer or they remove constraints from that consumer. So, if the service can be used effectively by the users to share their latest social media posts, for example, that would be considered utility. If the service is always up, meaning it has great warranty, but it doesn't perform the service that the customer wants it to do, meaning it hasn't gotten good utility, then the service is simply going to end up failing. You can't run a successful service without both utility and warranty