The final stage of the mission is close-out. All good things must come to an end and once Lucy’s mission has come to an end it will be time to put the spacecraft into a long slumber. Even after the spacecraft is turned off, Lucy is on an orbit that will likely remain stable for more than 600,000 years. Thus Lucy will continue to orbit between the Earth and the Trojan asteroids far into the future. Maybe some day humans will spread out into the Solar System and collect the Lucy spacecraft as a relic of the early stages of human explorations out into our Solar System. If no humans interviene then in the far distance future the Lucy spacecraft will either be flung out of the Solar System or will crash into the Sun.
During Phase F the team will make sure that all data is archived, that all lessons learned have been documented, and that the spacecraft is on a stable orbit that won’t allow it to hit any potentially habitable world (there is a less than 0.01% chance that Lucy will hit any planet at all). While this signals the end of the mission, scientists will continue to use the data collected by the Lucy mission to make discoveries for years to come.