When a divorcing couple has children, a well-written parenting plan that covers many contingencies often makes the process go smoother. It also makes life easier after divorce. Of course, life has a habit of dealing in the unexpected. Perhaps the parenting plan that you thought would hold up well in practice has not, or several years have passed. Your children are older, everyone's life situations are different, and maybe one of you is even dealing with a health issue.
In such situations, it is reasonable that you would want to change the parenting plan rather than rely on goodwill or "let's figure it out as we go" agreements. While they can sometimes be effective, it really is a big help to see everything down on paper. However, you may be wondering, "Do I have to go to court and get a judge's approval every time my co-parent and I make the change?" The answer is no unless the two of you disagree on the change.