Everyone is different in this world, which means everyone learns differently and execute differently. You may require classical music, a warm, toasty room, and a cup of tea while you study. Someone else may require complete silence, a chilly room, and no snacks at all. Studying alone allows you to set the perfect study environment so you get the most out of studying.
Studying alone also allows you to use the study tactics that are the most effective for your learning style. Some students learn best with flashcards, while others learn best when they reread chapters of others. For more information read the article.