Common website launch mistakes

Most launch problems aren't exotic—they're the same handful of avoidable mistakes, repeated across countless otherwise-well-built sites. Here's the condensed list of what most often goes wrong, and where to find the full checklist for each.

Technical mistakes

• Leaving a staging noindex tag or blanket robots.txt block in place after going live, which can quietly keep the whole site out of search results for weeks before anyone notices (see technical SEO)
• Forgetting redirects when URLs change, breaking every old bookmark, backlink and search listing pointing at the site (see technical SEO and site migration)
• No working, tested backup at the moment something actually breaks (see security)
• Letting the SSL certificate expire unnoticed, which can lock every visitor out with a browser warning (see security)
• Skipping a custom 404 page, leaving visitors stranded on a dead end with no way back
• Losing SPF/DKIM/DMARC records during a host or DNS change, silently sending every outgoing email straight to spam (see email deliverability)

SEO & content mistakes

• Duplicate or missing meta descriptions and title tags copied across every page instead of written per page (see SEO checklist)
• Thin or padded content written to fill space rather than genuinely help the reader (see content checklist)
• Inventing statistics or claims to make content sound more authoritative—a fast way to lose trust once anyone checks
• Ignoring internal linking, leaving important pages orphaned with no path leading to them
• Launching, then never updating content again—stale prices, dead outbound links and outdated information accumulate silently
• Structured data that doesn't match the visible page—an inflated rating or a price that doesn't match checkout (see structured data)

Design & UX mistakes

• Designing and testing only on desktop, then discovering mobile layout problems after launch (see mobile checklist)
• Touch targets too small or too close together to tap reliably on a real phone
• Intrusive pop-ups that are difficult to dismiss, especially on mobile screens
• Relying on color alone to convey meaning, which fails for colorblind users and anyone with a low-quality screen (see accessibility checklist)
• Forms that ask for more than they need, adding friction that quietly costs conversions (see conversion & forms)

Process mistakes

• Setting up analytics after launch instead of before, permanently losing the launch-period baseline (see analytics checklist)
• No second reviewer checking the site end to end before go-live—the person who built it is the worst-positioned person to catch what they've stopped noticing
• Treating launch as the finish line rather than the start of an ongoing maintenance routine (see maintenance checklist)
• No plan for who handles an incident—a security issue or outage discovered with nobody clear on the next step
• Migrating or redesigning without a redirect map, discovering broken URLs and lost rankings only after traffic has already dropped (see site migration checklist)

Compliance & communication mistakes

• Launching a cookie banner that doesn't actually respect the visitor's choice, still firing every tracker regardless of what was declined (see privacy & cookie consent)
• Never testing that transactional email actually arrives, discovering only after launch that order confirmations or password resets are landing in spam (see email deliverability)
• Nobody outside the build team reviewing the site before launch, so problems obvious to a fresh pair of eyes ship anyway
• No agreed rollback threshold for launch day, leaving the team improvising under pressure if something does go wrong (see launch day checklist)
• Secrets or API keys committed to a public repository, discovered only once something is already abused (see security checklist)
• Auto-translated pages published without human review, quietly making incorrect or embarrassing claims to an entire market (see international SEO checklist)

Every mistake above links back to its full checklist—work through the pre-launch checklist and launch day checklist to catch these before they happen, not after.