Perhaps it is attracted by grass a short distance away and then to some a bit farther away, thus separating itself from the flock.
يُدْرِكُ ٱلرَّاعِي إِمْكَانِيَّةَ شُرُودِ أَيٍّ مِنْ خِرَافِهِ عَنِ ٱلْقَطِيعِ .‏