Performance · 15 points
Lazy-loaded images
One check, stated three ways: what we measure, what would make it wrong, and how to confirm it yourself.
What this measures
How many <img> elements carry loading="lazy", against the total.
Where this check can be wrong
The first image above the fold should *not* be lazy, so a page that scores badly here may be configured correctly. Weighted at 2 for exactly that reason.
Verify it without taking our word for it
In DevTools → Network, reload and check which images start downloading immediately versus on scroll.