When I updated my https://Twitter.com profile pic:
Your image was not featured because the moderator believes it is a repost (copied from elsewhere on the internet without any creative changes added by you). To avoid this, create your own original content, or if you must repost images then submit them to a stream that allows reposts such as the Imgflip repost stream. We enforce this rule so people can find unique fun content on Imgflip instead of just the same content as every other social media website.