15 WordPress SEO Mistakes That Quietly Cost You Traffic

These are the mistakes I find most often when auditing WordPress sites. None of them are dramatic on their own, but together they quietly hold back rankings for months. Check your site against each one.

Indexing and setup mistakes#

1. “Discourage search engines” left on after launch. Check Settings → Reading on every live site.
2. Two SEO systems active — e.g. a theme’s SEO features plus Yoast — producing duplicate titles, descriptions or canonicals. View source and search for “canonical”.
3. Plain or date-based permalinks on evergreen content — see permalinks.
4. Staging site indexed, creating duplicate content — see staging guide.
5. Noindexed pages in the sitemap or important pages blocked in robots.txt.

Content and structure mistakes#

6. Hundreds of thin tags with one post each — see categories vs tags.
7. Several posts targeting the same keyword (cannibalization) instead of one strong guide.
8. Headings used for styling, with multiple H1s or skipped levels.
9. No internal links to new posts, leaving them orphaned — see internal linking.
10. Generic titles and missing meta descriptions on key pages.

Technical and performance mistakes#

11. Slow hosting and heavy page builders failing Core Web Vitals on mobile — see speed optimization.
12. Huge, unoptimised images and lazy-loaded hero images — see image SEO.
13. Changing slugs or deleting posts without redirects — see redirects.
14. Attachment pages indexed as thin content.
15. Outdated plugins leading to hacks and spam injection — see security.

A 30-minute audit#

For a deeper process, follow the SEO audit guide and the WordPress SEO guide.