Since the beginning of the IVR industry (that would be something like 30 years ago) the industry has been talking about "Call Containment." This is typically defined as the percentage of calls which end in the IVR and don't go to a person.
It's time to put a stake in the ground and declare the word "Containment" as forbidden in the customer service dictionary. Instead, the right phrase to use when talking about IVR performance is "Self Service."
"Containment" is a terrible, awful word which confirms all the negtive stereotypes of automated customer service. It leaves the impression that the design goal of an IVR is to put customers in a place they cannot escape from. And let's face it, we all know systems where that was the goal, stated or otherwise.
When you think in those terms, you also design and measure in those terms. A "Containment" metric only looks at whether a call stayed inside the IVR. It says nothing about whether the customer was served, or had a positive impression of the experience. About the only virtue of Containment is that it's easy to measure: calls contained divided by total calls.
"Self Service," on the other hand, contains the notion of service. If the customer was not served, then the IVR failed at self-service even if it succeeded at containment. Self-service is much closer to what both customers and companies actually want an IVR to do.
When you design and measure an IVR based on Self Service, you think in terms of empowering the customers to help themselves, rather than limiting their freedom to exit the system. Self Service is what we do at an ATM or when buying stuff online, and in many cases customers prefer it.
If you're in the customer service world, next time you're tempted to talk about "Containment" stop yourself and substitute "Self Service." And when you hear colleagues talking about Containment, you can try the phrase I use:
"Actually, I prefer the term Self Service, because it better reflects what we're trying to accomplish."