"If it ain't broke, don't fix it" is a phrase that is widely used and accepted in any circle of life. This pertains to the current makeup of the Golden State Warriors—and how rarely does anyone get to say that—because of their 22-12 record and playoff standing in the West.
If the team is playing well, succeeding on both levels on offense and defense, why is there a need for change?
Answer: there isn't any reason.
But with any team in basketball or in all of sports, there is always need to get better and to improve. Look across the Bay for example at the San Francisco 49ers who, despite making it to the NFC Championship Game and a 6-2-1 record, made the change at quarterback that Jim Harbaugh believed to be a necessary season-changing move.
Now, this isn't to say that there are any rotation changes to make that come close to that level of impact. However, there are many reasons to shuffle the front-end or back-end of a rotation because of performance-related issues or injury concerns.