玉たまに瑕きず

expression, noun

fly in the ointment; small flaw in an otherwise perfect thing; only fault

Idiomatic expression used when something excellent has one minor defect. Often used in the pattern ～が玉に瑕 or ～は玉に瑕.

• 彼かれは優ゆう秀しゅうだが、遅ち刻こくが多おおいのが玉たまに瑕きずだ。

  He is excellent, but his frequent lateness is the fly in the ointment.

• このホテルはサービスも部屋へやも完かん璧ぺきだが、駅えきから遠とおいのが玉たまに瑕きずだ。

  This hotel has perfect service and rooms, but the distance from the station is the only drawback.