expression
the shoemaker's children go barefoot; the dyer wears white hakama
Proverbial expression meaning that experts often neglect their own affairs or fail to apply their skills to themselves. Literally, 'the dyer's white hakama' (a dyer would normally wear dark, dyed clothes, but his own formal wear remains undyed).
彼は有名なシェフなのに、家ではいつもインスタント食品ばかり食べている。まさに紺屋の白袴だ。
He's a famous chef, but at home he always eats instant food. It's a classic case of the shoemaker's children going barefoot.
医者の不養生とはよく言うが、紺屋の白袴も同じようなものだ。
They often say 'doctors don't take care of their own health,' and 'the dyer's white hakama' is much the same.