In Agile, estimates are initially based on previous experiences or expert opinions, but as the team progresses through sprints, they gain more insight into the project's actual complexity and the team's capacity. Agile estimates evolve over time based on the team's velocity, which reflects how much work the team can realistically handle. This is why the actual scope and timelines can differ from initial estimates. The agile lead should emphasize that the initial estimates were helpful for understanding feasibility, but the true estimates are refined continuously as the team gains more experience and understanding of the work, and as complexities or dependencies become clearer during each sprint.