A WordPress site's poor performance almost always traces back to four root causes: slow hosting, unoptimized images, bloated code from plugins and themes, and missing caching. The right diagnostic approach is to check TTFB first (hosting issue), then LCP (image issue), then look at code bloat and caching. PageSpeed Insights scores are explained, including why mobile scores differ from desktop and what each Core Web Vital measures. The key takeaway is to identify the actual root cause before installing optimization plugins, since plugins can't compensate for bad hosting or multi-megabyte images.
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Why Speed Matters More Than You ThinkWhat PageSpeed Insights Is Actually MeasuringThe Four Root Causes of a Slow WordPress SiteWhere to StartThe Diagnostic Step Most People SkipSort: