Marriages that resulted from teenage dating
In cases where the marriage was part of the family's economic and social strategy, careful planning by the whole unit was needed, for a good marriage could bring considerable economic benefits.
The prospective bride and groom also had an economic stake in a marriage contract, because it would determine not only who their life partner would be, but also how well they could expect to live.
For most of human history, arranged marriages were the norm because "marriage" was less about the union of two souls and more about the union of two .
The rise of the "Marry for Love" ideal didn't really start in Western culture until the 16th century, and there are places on Earth where it still hasn't.
While the priority is, again, the union of two families, that union is dependent on the stability and comfort of the two people getting married, so the two families would try their best to come up with a Perfectly Arranged Marriage.
Most people don't really want to marry a total stranger (much less have sex with them), and if that total stranger turns out to be a complete rogue and a cad, it may be necessary for the heroes to spring into action and rescue the hapless member of their group who is being forced to walk down the aisle.
(Of course, being Big Damn Heroes, they'll have to do so in the most overblown and dramatic way possible.) Sometimes, the person in the arranged marriage takes matters into their own hands and becomes a Runaway Fianc.
The couple's happiness just wasn't the goal the way it is in Western marriages today.
However, the one thing that is almost always present in an arranged marriage is tension.
The Church currently disavows any practice of polygamy; however, the eternal doctrine of plural marriage is still in place.