If you view videos while logged in to your YouTube account, YouTube collects information on the kinds of videos you like to watch and, over time, compiles lists of videos to recommend to you. YouTube displays this video in a large gray bar if you click the "Recommendations" tab in the homepage. Because this technology is a work in progress, YouTube may display videos you don't want to see, and concurrently displays the details of your viewing history that lead YouTube to make the recommendations. Fortunately, YouTube allows you to clear this information and get rid of the "Recommendations" bar right from the homepage.
Log in to either your YouTube account or the Google account associated with your YouTube account, depending on the type of account you created. Click the "Sign In" link in the upper right corner.
Locate the recommendation bar in the middle of the YouTube homepage by clicking the "Recommendations" tab in the sub-menu across the top of the left section of the page. This displays the Recommendation bar on the homepage, if it wasn't already displaying.
Click the small "X" in the upper right corner of the recommendation bar, directly opposite "We've Found Some Channels You Might Like." This gets rid of the YouTube Recommendation bar immediately.