Digital single without an MV and promotion not doing well on charts, who would have thought? They dropped the single on their 10th anniversary and moved on with their life. It's your fault thinking that such a song can do well.
Going by your logic BP's the girls and ready for love are flops too because they didn't do well. It seems that you expect that singles that artists just drop and don't promote own the charts. In this case songs have mv's but it changes nothing, they are umpromoted singles.