Automatic reclustering is a Snowflake feature designed to maintain the efficient organization of data within tables based on specified clustering keys. Over time, as data is inserted, updated, or deleted, the physical arrangement of data can become fragmented, leading to inefficient query performance. Automatic reclustering works in the background, without requiring direct intervention, to reorganize the data and ensure that it remains optimized for query access. This process helps maintain consistent performance by reducing the need for full table scans and improving the efficiency of data retrieval.