Lazy loading delays the fetching of offscreen images, iframes, videos, and backgrounds until they are
about to enter the viewport. This reduces the number of requests during the critical rendering path and
focuses bandwidth on above‑the‑fold content. The net effect is a faster perceived load and often
measurable improvements in Core Web Vitals like LCP and CLS when implemented correctly. WP Lightning
Load can lazy load multiple media types and supports responsive images (srcset) to ensure
the browser still picks the best size at the moment of display.
However, it’s important to exclude elements that are crucial to your first impression, such as hero
banners, prominent product images, or brand logos in the header. These should render immediately to
avoid flicker or visual gaps. You can exclude them using CSS selectors in the plugin’s settings—for
example, .hero img or header .site-logo img. Be careful with elements that
rely on an immediate size allocation, like sliders and carousels. If a container has no intrinsic height
and the image is lazy loaded, the page may shift when the image appears, increasing CLS. Provide
aspect‑ratio boxes or placeholders to keep layout stable before images load.
Finally, avoid double‑lazy by ensuring only one system is applying lazy loading. If your theme or another
plugin already adds lazy attributes, consider disabling one source to prevent conflicts. Test on mobile
and desktop, including slow network conditions, to validate behavior across contexts.