The phrase "different trajectories" means that two or more things are moving or evolving in separate paths or directions. They are not following the same course or ending up in the same place. Full definition
Scientists will merge «shared socioeconomic pathways» with different trajectories for levels of greenhouse gases over the century, based on how the planet slows the burning of fossil fuels. (climatechangenews.com)
While education reform has taken a slightly different trajectory following the appointment of Theresa May as Prime Minister, who has since put forward proposals to lift the ban on grammar school in England, Education Secretary Justine Greening has reaffirmed the government's commitment to academies and suggested that they will still be a central part of education policy. (educationbusinessuk.net)
You can see that each of them has a different amount saved, because their goals are on very different trajectories in terms of time horizon. (chiefmomofficer.org)