がったり三さん両りょう

expression

even small mistakes can be costly

Proverb warning that a seemingly trivial error (here, a loss of just three ryō) can lead to significant trouble. Used to caution against carelessness.

• 「がったり三さん両りょう」ということわざがあるように、ちょっとした油ゆ断だんが大おおきな損そんにつながることもある。

  As the proverb "gattari sanryō" says, even a small lapse in attention can sometimes lead to a big loss.