Relevant, subcategorized playlists can greatly boost user engagement. When viewers are in a playlist, they will see a list of videos in it while watching the current video. They can then navigate through the playlist. It makes it easy to share multiple videos at a time, by sharing a link to the playlist instead of one video.
This format provides a more immersive channel experience, and curating great playlists can have a greater impact than creating videos. Playlists are heavily promoted by YouTube, and your video is more likely to be viewed as part of a playlist than on its own in YouTube’s ecosystem.