1. A method performed by a computer for managing performance of an information technology service delivery process, comprising: collecting, by the computer, key performance metrics of a service delivery process in a continuous manner at defined time intervals; applying, by the computer, a change to the service delivery process at one of the defined time intervals, wherein the change is applied to enable the service delivery process to meet a set of performance objectives; responsive to applying the change to the service delivery process, continuing to collect, by the computer, the key performance metrics of the service delivery process at the defined time intervals, wherein key performance metrics collected prior to applying the change are baseline performance measurements, and wherein key performance metrics collected after applying the change are post-change performance measurements; generating, by the computer, a process behavior graph of the service delivery process comprising an x-axis representing the defined time intervals and a y-axis representing key performance metric values, wherein generating the process behavior graph further comprises: displaying each baseline performance measurement and post-change performance measurement collected on the process behavior graph at a time interval collected and at the key performance metric value measured; displaying a visual indicator representing the time interval in which the change was applied to the service delivery process on the process behavior graph; displaying a visual indicator representing the set of performance objectives for the service delivery process on the process behavior graph; and displaying, by the computer, the generated process behavior graph to a user.