Why is it important to place the match stage early in an aggregation pipeline?

Placing the match stage early in an aggregation pipeline is crucial because it leverages indexes effectively, which can result in significant performance improvements. When the match stage is executed first, it filters the documents early on in the pipeline. This means that only the documents relevant to the query need to be processed in the subsequent stages of the pipeline, thereby reducing the overall number of documents that these stages need to handle.

By minimizing the number of documents that flow through the pipeline, you decrease the computational resources required for further operations such as group or sort stages. This leads to faster query execution and lower latency, making your application more responsive.

Additionally, utilizing indexes during the match stage can drastically speed up the filtering process. If the match stage is placed later in the pipeline, the number of documents handled by the stages before matching could be large, making the entire pipeline less efficient. Therefore, incorporating the match stage early in the aggregation pipeline is a best practice that enhances both performance and resource utilization.