This is a legacy of coverture. Under the legal doctrine of coverture, a woman became a femme covert. This meant husband and wife did not exist as legally distinct people. So any debts a woman contracted would be the responsibility of her husband, as if he had contracted them himself. While this undoubtedly invested ultimate authority in the husband, it was generally presumed a woman was acting with her husband's permission. Thus, while she could not legally contract debts without his permission, she could effectively go to a store and buy something on credit in his name (for example). There was no verification: the shopkeeper was allowed to take it on faith the woman had her husband's permission. These were notices not to extend her credit.

Such notices were effective in two ways. First, it discouraged shopkeepers from offering her credit. Second, it established the man's wife was not acting with his consent. This was not an ironclad defense: a man was expected to control his wife and failure to do so did not free him from his obligations. But it gave the husband support in arguing an extraordinary circumstance.

By the late 19th century, virtually every state had passed acts giving women independent property (and thus freed the husband from direct responsibility for her debts). However, the community property doctrine held that spouses in general were responsible for their spouse's debts. (As, indeed, they still are in such states.) Most states continued to make spouses responsible for their significant other's debts. Since men were the vast majority of breadwinners at the time this mostly meant men for women's debts. So these notices continued on in basically the same cultural context. The most common circumstances were abandonment (where the wife left but remained legally married) or a spendthrift wife.

Such notices declined precipitously in the 1960s and '70s. This was partly due to women's increasing economic power and feminism. Increasingly, women had their own money and social assumptions that the husband was responsible for his wife's debts weakened. Another big factor was the liberalization of divorce law. Being a spendthrift was not grounds for divorce, but no-fault divorces meant that men could divorce spendthrift wives. Abandonment was a reason for divorce, but the process could be complex and expensive. With no fault divorce, women who abandoned their husbands would generally find themselves divorced quickly and easily.

There are two different ways that a wife could legally enter into contracts (for instance purchases on account) for which her husband was responsible. These are by "agency" or by "dependency".

An agent is a person authorized to enter into contracts on behalf of another person or organization. Those contracts are binding on the authorizer and not on the agent. The authority must be granted by the person on whose behalf the agent is acting but the authorization may be granted in a number of different ways. For instance; directly, or by appointment to a position which would normally hold that authority (e.g. a purchasing officer) or by the regular behavior of the authorizer by normally paying the debts entered into by the agent. In a culture where the wife usually manages the household and does the regular household shopping, including things like clothing for herself, her children and her husband she would be acting as her husband's agent, authorized both by holding a position which normally holds that authority and by her husband's normal behavior of paying those debts.

Agency can be cancelled by the authorizing party giving constructive notice to effected parties that the agent is no longer acting on his behalf. These Personals notices would be one element of giving notice.

"Dependency" occurs where one person is legally responsible for meeting the basic needs such as food, accommodation, clothing and schooling etc. of another person. In most jurisdictions wives and children are dependents of the husband. This means that if a wife purchases basic needs from a vendor the husband must pay. The vendor can successfully sue the husband despite any notice the husband may have given because the husband cannot avoid the obligation.

Whether particular items are basic necessities may depend on the court's assessment of what is necessary for the "station in life" of a particular family.

The effect of this type of notice is not quite legally useless but it is legally limited. The practical effect would be to limit the amount of credit a vendor would be prepared to extend to the wife and cause the vendor to check with the husband before significant purchases.