I will talk about women only on basis of my experiences in Bangladesh.
In the middle-incomed people, there are many varieties. Like some live near to poor, some in between and some are near to rich and then they act differently too.
In Bangladesh and in other south Asian countries, the Grooms family doesn't say directly but always expects furniture and other gifts (Gold ornaments mainly) from the bride (There are a few exceptions also) or her family.
So, when a baby girl gets born, the girl's parent started saving money that will be needed when she will grow up and get married. Sometimes parents need time to save a big amount of money so they had to wait to get their daughter married. Or find it difficult to find a groom who will say yes, with a comparatively small amount of money. Especially if the girl's skin colour is not fair enough.
Some parents wanted to get their girls married before they pass master's degrees. Because of two reasons. One it will be difficult to find a groom with the same or more educated. And generally, in South Asia, men don't want to get married who are more educated than them. Probably they believe it will show them less masculine and more educated girls will be difficult to manage (Make them listen always). No one likes a woman who raises their voice. In this situation, parents will find it difficult to get a groom for their girls.
The other reason is people then think, the girl becomes aged. All over the world, there is a fascination with girls' ages. If somehow it goes near 30, the girl is marked as an aged woman and not good for the marriage market. In Bangladesh, if she gets a master's degree, some groom and their families will take it as a benchmark of becoming too aged to be selected as a bride. So, the girl's parents hurry to give their girls marry.
Another middle-class trend is to make their girl educated till they got a master's degree and then let them take a job. Then they will get married. Because if they don't get a job and get married. Then after getting married or after having a child, it will be difficult for them to get a job. In Bangladesh, age is a big factor to get a job. When a woman gets involved with household work, it is difficult for them to go out and do the job. Because their in-laws (Most grooms in Bangladesh live with their parents and then get a wife, and then make her or expected her to take care of the husband's parent, people believe it is the girl's job to take care of the groom's parents. Not her own parents or neither groom help to take care of his own parent) and husband are used to taking their service in the home, now they don't want to sacrifice their facilities or if they don't need money from the bride. So, for the bride, there won't be any income source and always have to live with the mercy of her groom and his family to get some money. And there won't be any aim in life except household work.
Some get jobs before marriage because they know, it is difficult for a grom to manage a family with their own income, so they look for a bride who earns. So, a job could be an asset for some girls to get married.
Some Muslim families don't let their girls wear hijab. Because they think, maybe the groom's family won't like it and then will face difficulty to marry their girl. So, they wait, after marrying if their husband or his family allows, then they will wear a hijab or head scarf.
Some parents give their daughters married earlier because of their safety. If the girl is beautiful, the surrounding men will make their life difficult. In that case, parents have no choice.
Some families give their older daughters marry early. Because otherwise if all girls became adults then people will mark it as a negative point that for some reason, no girls could get marry, all are becoming aged women (Not suitable for a bride). After the older daughter, they can wait and make other girls well educated before marrying.
