In more detail
Cannibalisation often builds up over years. A business publishes a service page, then a blog post on the same topic, then a "guide" and a landing page for a campaign, all aimed at much the same search. Each page gets a share of the links and attention, and none becomes the clear best answer.
Signs of cannibalisation include:
- Search Console showing several of your URLs receiving impressions for the same query, with the ranking URL changing over time
- A blog post outranking the service page you'd rather people saw
- Rankings that fluctuate without obvious cause
Not every overlap is a problem. Different pages can legitimately rank for related searches if they serve different intents, such as a pricing page and a how-to guide. Large sites often rank with two results for the same query. The issue is when pages are near-duplicates competing for the same intent.
Typical fixes are to consolidate the content into one stronger page and 301 redirect the others; to differentiate pages so each has a distinct purpose; to adjust internal links so the preferred page is clearly the main one; or, for true duplicates, to use a canonical tag.
Why it matters when hiring an agency
Consolidating competing pages is often one of the fastest ways to improve rankings on an established site, because it combines signals that already exist. A good agency will look for it during the audit using your own Search Console data.
Be careful with mass deletion. Ask the agency to show which pages compete, what traffic and links each has, and where each will redirect. Content that still earns links or conversions should be merged, not simply removed.