Google changes your meta description in roughly 70% of search results because its algorithm thinks it can serve the searcher better by pulling text directly from your page. This happens for several concrete reasons. First, query matching. If someone searches "Ottawa SEO pricing 2025" and your meta description says "We offer affordable SEO services," Google might grab a sentence from your pricing page that actually mentions rates or packages. The rewrite aims to show the searcher exactly what they typed. Second, technical triggers. Google ignores your meta description when it's under 50 characters, over 160 characters (gets truncated anyway), stuffed with keywords, or completely missing. Duplicate descriptions across multiple pages also get rewritten because Google knows they can't all be accurate. Third, content mismatch. If your description promises "complete WordPress migration guide" but the page is actually a sales pitch for migration services, Google pulls representative text instead. The algorithm cross-references your description against page content, headings, and structured data. Fourth, freshness and context. For news or time-sensitive queries, Google often pulls the most recent relevant snippet even if your meta description is well-written, because recency matters more than your static tag. At Ottawa SEO, we still write meta descriptions for every important page because when Google does use them, they control the message and usually improve CTR by 2-5% over algorithmic rewrites. We keep them between 140-155 characters, front-load the primary keyword naturally, include a clear value proposition, and make sure they honestly reflect the page. For our portfolio sites, we also check Search Console's Performance report filtered by page to see which descriptions Google is actually showing, then test refinements on underperforming pages. You can't force Google to use your description, but you can make it the best option available.