SEO is not a set-and-forget effort. You need ongoing updates because Google's algorithm changes roughly 500–600 times per year, competitors publish new content, and user behavior shifts with seasons and trends. The question isn't whether to update, but how to prioritize what needs attention and when. For most businesses, monthly content refreshes work well. Review your top 20 traffic pages each month and update statistics, expand thin sections, add new internal links, and refine meta descriptions based on current click-through rates. Quarterly technical audits catch crawl errors, broken links, and Core Web Vitals regressions before they accumulate into ranking losses. At Ottawa SEO, we run full technical checks every 90 days across our portfolio and immediately when Google announces a core update. Immediate updates are necessary when you experience sudden traffic drops, when Google rolls out a confirmed algorithm change, or when a competitor outranks you for money keywords. These situations demand same-week diagnosis and response. You cannot wait for the next quarterly review when revenue is bleeding. Content decay varies by topic. News-related pages lose relevance in weeks. Evergreen guides about foundational concepts might stay strong for 12–18 months. Local SEO requires updates whenever your NAP changes, you add services, or Google Business Profile features evolve. E-commerce sites need weekly product updates, seasonal keyword targeting, and constant schema markup adjustments. Monitoring frequency should exceed update frequency. Check Google Search Console weekly for coverage issues and query performance. Track rankings for your top 50 keywords at least bi-weekly so you catch negative trends before they compound. Most rank tracking tools automate this, so there is no excuse for monthly-only visibility. The practical rhythm for a mid-sized site: weekly monitoring, bi-weekly minor optimizations, monthly content updates, quarterly technical audits, and annual strategy overhauls. High-competition niches compress this timeline. Neglected sites that go six months without updates typically lose 15–30% of their organic visibility, and recovery takes double the neglect period to regain lost ground.