Peoplesoft system is under the pressure of constant change, which includes new software features, fixes to existing software or hardware issues, changes to business requirement.
Change is good. Change is advanced. Change is necessary
Change is disruptive. Change is expensive. Change is time-consuming. Change is risky.
After Peoplesoft 9.2 there is going to be no major upgrade again. Peoplesoft Selective adoption changed the way PeopleSoft application is maintained. Now features are delivered on a regular basis and customers do not need to upgrade the Application, instead they can decide what to apply and when to apply the features.
Whenever a change is applied there is always a chance that something existing might break. Most organizations have adapted to system-wide testing to identify what breaks when the change is applied. The largest portion of the cost is spent on this testing apart from the custom development cost. The changes that are applied are smaller and more focused but we need to apply them more frequently resulting in an increased amount of time and effort spent on testing.