I've got a lovely wife who's a professional photographer, three lovely grown children, a lovely old dog with bad hips and a good disposition, and an old house which is always in desperate need of repairs. My wife says that’s because the shoemaker's kids always go barefoot and the carpenter’s house always has a leaky roof.
2004, Yuichi Mori, Handbook of Computational Statistics: Concepts and Methods, Springer, →ISBN, page 498:
Traditionally, ‘the shoemaker's children go barefoot’; i.e., users of computational statistics ignore statistical issues—such as sensitivity analysis—of their simulation results.
2005, Michka Assayas, “Faith Versus Luck”, in Bono: In Conversation with Michka Assayas, New York: Riverhead books, →ISBN, page 309:
So we eventually listened to the unfinished studio CD through his daughter Eve's ghetto blaster. I made the predictable joke about the shoemaker's children who always go barefoot. It had been the same at Elton John's place, Bono revealed.
2022, Valerie Schultz, A Hill of Beans: The Grace of Everyday Troubles, Liturgical Press, →ISBN, page 17:
Just as the shoemaker's children go barefoot and the carpenter's children live under a leaky roof, I knew this day would come. I am a church worker whose child has stopped going to church.
Hokkien: 燒瓷的食缺，織蓆的睏椅／烧瓷的食缺，织席的困椅(Sio-huî--ê chia̍h khih, chit-chhio̍h--ê khùn í, literally “Potters eat out of chipped bowls; mat weavers sleep on chairs.”)
Japanese: 紺屋の白袴(ja)(こうやのしろばかま, kōya-no shirobakama, literally “a navy blue shop's white skirt”), 医者の不養生(ja)(いしゃのふようじょう, isha-no fuyōjō, literally “the doctor's neglect of his health”)
Persian: کوزهگر از کوزه شکسته آب میخورد(kuze-gar az kuze šekaste âb mi-xorad, literally “The potter drinks water from broken pots.”)