FrontendHaltPerformance·Advanced·Conceptual·1 min read
What's the trade-off of aggressive image lazy-loading?
Short interview answer
It saves bandwidth and defers work for offscreen images, but applied to above-the-fold or LCP images it delays exactly what the user is waiting to see. It also needs a reserved space or it causes layout shift when images pop in during scroll.
Key takeaway
Explain the underlying mental model clearly, then support it with a concrete example and its trade-offs.