Yandex's mission is to find the answer to our users' questions. Furthermore, the answer should not only be relevant, but also accessible. For example, users should not encounter excessive pop-ups or advertising whilst trying to make sense of overcomplicated texts.
Unfortunately, webmasters sometimes forget about intuitiveness and usability when developing sites. Therefore, we've developed a special algorithm that can determine how useful specific page elements are, and give preference to user-friendly sites in our search results.