Keyword cannibalization. It happens to the best of us.
What is keyword cannibalization, you ask?
Simply put – keyword cannibalization is the common term used for when several different pages on the same website contain the same or similar keywords and phrases, causing confusion for search engines as to which page is intended to fit for each query. This often results in those pages "swapping" impressions in the SERPs as search engines try to determine the most fitting of them for that search term. It has the power to ruin any content marketing strategy.
When your content is competing with itself, your rankings suffer. This happens unintentionally to even the biggest sites with the best search engine optimization (SEO) experts – so don't feel too bad if you come across a cannibalization problem of your own.
Luckily, identifying a cannibalism problem isn't difficult – especially with the right keyword tools – and there are some easy ways to stop your content from eating itself up.