Which position change will potentially lead to a higher traffic boost?

Moving from position 11 to 10 is likely to provide the most significant traffic boost because it crosses the threshold into the top 10 search results, which are displayed on the first page. The first page of search results receives a disproportionately high percentage of clicks compared to subsequent pages. While moving from 51 to 30 or 91 to 40 represents a larger numerical jump, these positions are still typically on later search engine results pages (SERPs), which receive far less user attention and clicks. The visibility gained by reaching the first page (top 10) is a critical factor for increasing organic traffic.