Amazon Q Not Uniformly Crawling Multiple Sources Specified in "Source URLs

I've been working with Amazon Q's "Source URLs" feature to crawl multiple specified URLs. However, I've observed that Q often retrieves content from only one or two of the provided sources, rather than evenly crawling and suggesting the best content from all the specified URLs.

Is there a known reason for this selective content retrieval? Are there best practices I should follow when adding multiple URLs to ensure a more uniform crawl across all provided sources?

Appreciate any insights or guidance on this matter.