In institutional churches, people normally solve their disputes by simply leaving one church and going to another, where the pastor, who wants to build his kingdom at any cost and who has no real relationship with other pastors, welcomes such people and sides with them as they relate their woeful tales. This pattern effectively neutralizes Christ’s commanded steps of reconciliation. And normally, it is just a matter of months or years before the offended person whom such pastors welcomed into their church has left to find another church, offended once again.
Jesus expected that churches would be small enough to fit into homes, and that local pastors/elders/overseers would be working together in one body. Thus the excommunication of a member of one church would effectively be an excommunication from all the churches. It is the responsibility of each pastor/elder/overseer to ask incoming Christians about their former church background and then contact the leadership of their former church to determine if such people should be welcomed.