Change the main query on your site to only load in 10 items and no more than that. You can have multiple queries, but most sites load in a single query that is needed to load in all the content of the page. This can take thousands of milliseconds to render more content based on the number of items.
I’ve worked on some very large websites that request 100’s of items and found that it doesn’t matter the database construction you really shouldn’t overload the database to work that hard, and after the page is cached the database will become idled waiting for another request.
There isn’t really a visual to show that this feature works however I would test it out on your theme as some themes might have multiple queries merging in object which will make this not work correctly, but in terms of freeing up memory and requests this is a good solution for those who might be stumped making there websites faster.