Left raise-hand radical anchors 损 in the manual-action family - handling, hurting, reducing - alongside 抢 (to grab), 挖 (to dig). The hand carries the active verb force.
Right 员 supplies the sound - yuán drifting to sǔn through a vowel-and-onset shift that's opaque now but regular historically. Same phonetic frame appears in 陨 fall, 损 harm, 殒 perish. Combined with hand, 损 reads "to reduce or damage by handling": 损失 loss, 损坏 damage, 损害 harm.
