The Yom Ha'din or Day of Judgment of Rosh Hashanah is concerned with continuity in the matter of our efforts and whether there is more to accomplish. The Day of Judgment after death is a determination of what was accomplished and and whether enough was accomplished or if there is a need to repair or improve anything. The Day of Judgment of the year 6000 is the final one because it is concerned with whether or not the repair was accomplished within the allotted time. At the end of 6000 everything is taken into account, including things that took place after death. After the Day of Judgment, this world will no longer exist because it is the day when everything and everyone is judged for merit to enter the World to Come. Those who merit to go may begin the process. Those who do not merit cease to exist.