There’s certain things that are comforting by virtue of having done or seen them many times before and thus you know exactly what to expect.
Diablo III is like that for me, specifically the story mode. The original Diablo III had you go through the (very linear) story multiple times, once for each difficulty level, and by the time you hit the maximum level of 60 you’d generally done it at least three or four times. Combine that with the five different classes you can choose, and that’s a lot of repeats. When the Reaper of Souls expansion came out, Blizzard did away with that whole repeat-the-story-many-times in favour of Adventure Mode. It’s varied and certainly less repetitive than the old story mode, but I do enjoy going back every now and again and starting a new character to play through the story from the beginning. It’s definitely comfortable.