When Instagram is deciding which users deserve to have their videos displayed widely on the platform, IG's algorithms certainly consider the metrics most people know are important: followers, likes, and video views. But they dig much deeper than that. The system also looks for content that engages its audience. And users' comments are a critical measure of how engaged they are with the videos they watch. Highly-relevant comments elevate the importance of a post in Instagram's eyes, signaling the system that the video (and the poster's account) should be given more exposure. Just as importantly, relevant comments will stimulate discussion — creating large-scale engagement with the post and boosting its significance to IG's algorithms even more.