expression
don't let your guard down after a victory; tighten your helmet strings after winning
Proverb warning against complacency after success; literally 'after winning, tighten the strings of your helmet'.
試合に勝ったからといって、勝って兜の緒を締めよの精神で次の練習に臨もう。
Just because we won the match, let's approach the next practice with the spirit of 'don't let your guard down after a victory.'
A traditional Japanese proverb derived from samurai culture, where a warrior was advised to retighten his helmet cords after a battle to stay prepared for unexpected attacks.