expression
good advice may be hard to take; good medicine tastes bitter
Proverb meaning that honest, helpful criticism or advice can be unpleasant to hear, just as effective medicine often tastes bitter.
彼の忠告は厳しかったが、良薬は口に苦しというから、素直に受け入れた。
His advice was harsh, but as they say, good medicine tastes bitter, so I accepted it honestly.
A classical Japanese proverb derived from a Chinese saying. The exact historical origin is uncertain, but it has been used for centuries to express the idea that beneficial things are often unpleasant.