Whom do girls never marry, according to Algernon?

In Act 1 of The Importance of Being Earnest, which takes place in Algernon Moncrieff’s Flat in Half-Moon Street, Algernon is having a conversation with Ernest Worthing (Jack). Algernon explains that Aunt Augusta would not approve of Jack being there. When Jack asks why not, Algernon responds "My dear fellow, the way you flirt with Gwendolen is perfectly disgraceful. It is almost as bad as the way Gwendolen flirts with you." To this, Jack responds that he is in love with Gwendolen and intends to propose to her. Jack also expresses that he finds Algernon's views on marriage "utterly umromantic." Algernon states that he does not believe Jack and Gwendolen will ever be married, and he explains that he believes this because "girls never marry the men they flirt with. Girls don’t think it right."
Later in Act 1, Algernon discusses his contempt at being seated next to a woman named Mary Farquhar at dinner parties. He doesn't wish to sit near her because she "always flirts with her own husband across the dinner-table." Algernon finds this extremely distasteful.
Based on these quotes from the text, Algernon is shown to have traditional, non-emotional views on marriage. He believes that marriage is a social contract rather than a celebration of love. In this context, Algernon does not believe women ever marry the men they flirt with, because flirting implies a physical or sexual attraction, which Algernon does not believe is the base of a marriage.
These views are consistent with the social views at the time. This play was published in 1895, at which time the social climate was that women married for safety and security and to have children, not for emotional reasons.
See the link below for additional information regarding gender roles in the 19th century.
https://www.bl.uk/romantics-and-victorians/articles/gender-roles-in-the-19th-centur

Algernon tells Jack that girls never marry the men they flirt with. For this reason, he is fairly sure that Jack will never end up married to Gwendolen, because the two of them have an ongoing flirtation. Of course, Algernon is probably being flippant with this remark. He goes on to explain that he is actually rather concerned about Jack's intentions towards Gwendolen because she is Algernon's cousin and he does not give his "consent" to whatever Jack plans to propose to her. Algernon has previously expressed views opposed to traditional marriage, stating that divorces are "made in heaven," and seems to be encouraging the suggestion that marriage does not spring from romance, but rather, from necessity. Girls do not marry the men they flirt with; they flirt with men who interest them, but they are required to marry men who will offer them a foothold in society or a good household, rather than men who are flirtatious bachelors.