Most divorce cases are settled out of court. If the case goes to court, then a judge makes the decisions. Even if both spouses object to the ruling, they will have to return to court to make changes. This takes time.
This article lists some of the important documents that you will want to have ready to bring to mediation.
Angry spouses sometimes leave the decisions about their children in the hands of the judge. But the judge doesn't know or love your children, so why would you want them to make such important decisions?