In our ongoing efforts to make webpages load as fast as possible it’s important that we don’t just look at file sizes and aesthetics but also the order in which pages load in a browser. For example, would you rather your page stayed blank while all the content is loading, or would you rather it was loaded in stages? (logo first, then page content, followed by any animation or slideshows?)
The important thing to remember is that while a page that loads in stages isn’t ideal, it at least shows the person visiting your website that something is actually happening. The danger with a site that waits for all its content to load before displaying it is that a large script could take 4-5 seconds to show on your page. Is the visitor going to wait for that? Will they think the page is broken and give up?
The following is a simple extract from an article written by UXMovement.com about how to easily speed up the loading times of your sites pages:
Making users wait to see your site and showing them incorrectly formatted content is not a good user experience. Follow this best practice with your code, and your users should have no complaints about the speed of your website.