What is a primary downside of creating large documents in MongoDB?

Creating large documents in MongoDB can indeed reduce performance, which is the primary downside. When documents grow too large, it can lead to several performance-related issues. For example, large documents can consume more memory and disk space, affecting how efficiently data can be read and written. This can lead to increased I/O operations because the system may have to load and handle larger amounts of data at once, which can slow down the retrieval and updating processes.

Additionally, MongoDB has a document size limit (currently 16 MB), and managing documents that approach this limit can complicate operations like indexing and querying. Large documents might also lead to performance bottlenecks in applications that access these documents frequently, as the overhead of handling large payloads can impact the overall speed of data operations.

On the other hand, smaller, well-structured documents typically allow for more efficient data handling and retrieval, improving overall system performance.