Which user action on a Reel carries the greatest weight in signaling positive interest to the Instagram algorithm?

On a Reel, the user action that carries the greatest weight in signaling positive interest to the Instagram algorithm is when a user watches the Reel to completion and then re-watches it (looping). This indicates that the user found the content highly engaging and worth experiencing multiple times. While likes, comments, and shares are valuable signals, a complete re-watch suggests a deeper level of interest and enjoyment. The algorithm interprets this as a strong indication that the Reel is captivating and relevant to the user's preferences. For example, if a user watches a 15-second Reel and then it immediately loops and they watch it again, this signals stronger interest than simply liking the Reel. High watch time and looping rates are key factors in determining the visibility of Reels in the Reels feed and on the Explore page.