Encore rides are pre-recorded rides that are being re-shown in the live workouts schedule. Since they are pre-recorded (usually in the last few days), there is no chance for new athletes to get a shout-out from the instructor. However, since they appear on the live schedule, these rides or runs usually have more athletes take part, resulting in a larger leaderboard. Also, stats & output on the leaderboard are tracked similarly to a live ride - everyone starts at 0 when the class starts (compared to an on-demand ride where you see people's stats at various points of their own ride). This means you can compete with everyone in the class on the leaderboard.