How does lazy loading reduce the impact on website performance?

Lazy loading reduces the impact on website performance by delaying the loading of scripts until they are actually needed. This approach is particularly beneficial for improving page load times, as it allows the initial rendering of the webpage to occur without waiting for all scripts to load. When scripts are loaded only when they come into the viewport or are triggered by user interaction, it minimizes the amount of JavaScript that needs to be processed upfront, which can significantly speed up the perceived performance of the site.

By not blocking the main thread with unnecessary script loads, lazy loading ensures that users can interact with the content without experiencing delays, resulting in a better user experience overall. This strategy also helps conserve resources, as scripts that are not used often do not burden the loading process, thereby enhancing the efficiency of web applications.

In contrast, loading all scripts at once could cause a slower initial render and increase the time it takes for users to see the content. Compressing scripts into a single file may optimize loading time to some extent but doesn't specifically address when the scripts are loaded. Caching scripts can improve load times on subsequent visits but doesn’t prevent performance impacts during the initial load.