Why images dominate page weight
On most content and ecommerce pages, images account for the largest share of total page weight — often more than every script and stylesheet combined. That makes image delivery the highest-leverage place to cut load time without touching a line of application code.
WebOptiva's audit measures this directly: original image bytes versus optimized delivery bytes, plus the resulting load-time improvement, so the opportunity is quantified rather than assumed.
Format matters more than most compression sliders
AVIF and WebP routinely deliver the same visual quality as JPEG or PNG at a fraction of the file size, because they use modern compression algorithms designed specifically for photographic and UI imagery.
Quality settings still matter within a format — but choosing the right modern format first typically saves more bytes than aggressively lowering a JPEG quality slider and risking visible artifacts.
Responsive sizing avoids sending more than the browser needs
A 2400px-wide hero image served to a 400px-wide mobile viewport wastes bandwidth regardless of how well it's compressed. Responsive `srcset`/`sizes` delivery — plus device-pixel-ratio-aware variants — ensures each visitor downloads an image sized for their actual viewport, not a one-size-fits-all original.
Combined, modern-format conversion and responsive sizing are the two changes most likely to produce a measurable, visitor-facing speed improvement without any perceptible loss in visual quality.