The drill-down feature in Power BI dashboards allows users to explore data in greater detail by clicking on visual elements, such as charts or graphs. For example, a bar chart showing total sales can be drilled down to reveal sales by region or individual products. This interactive capability helps users investigate underlying data without needing to leave the dashboard or generate new reports. It enhances data exploration and understanding by allowing users to navigate from high-level summaries to more granular insights, promoting deeper analysis of key metrics.