Compare Maggie and Dee based on their motivations, personalities, and feelings about heritage.
Early on in the story, Mama says,
Maggie will be nervous until after her sister goes: she will stand hopelessly in corners, homely and ashamed of the burn scars down her arms and legs, eyeing her sister with a mixture of envy and awe. She thinks her sister has held life always in the palm of one hand, that "no" is a word the world never learned to say to her.
Dee is confident, even arrogant, while Maggie is uncertain. Dee looks people directly in the eyes while Maggie looks down, keeping her eyes on the ground rather than meeting the gaze of other people. Dee is beautiful and educated and stylish, and Maggie is homely and nervous. Dee lacks a real understanding of her family heritage; she doesn't know most of the stories that go along with the items she wants to take home with her. Maggie knows which family member made what and when, and Mama and Maggie still use the items that Dee wants to take. Moreover, she doesn't want to take these items so that she can use them, as her mother and sister do; she plans to make a centerpiece from one and will do "something artistic" with another.
When it comes to the quilts, Dee accuses Maggie of being "'backward enough to put them to everyday use.'" Dee plans to take the quilts—quilts she'd rejected several years earlier—and hang them on her wall. Maggie would, indeed, use them for the purpose for which they were intended: to put on a bed. Now, Dee calls them "'priceless,'" and she seems to think of them as artifacts of something past, something dead and gone. However, for Mama and Maggie, the quilts represent a heritage that is kept alive, that is still present because they use the items made by family every day.
Dee is motivated by her desire to climb higher on the social ladder. She sees the old items at home that used to be embarrassing to her now as items to "display" in her urbane and up-to-date decorations in her new place. She is aggressive and tries to push both her mother and Maggie around so that she can get what she wants out of them. She sees her heritage in terms of material possessions and changing her name for more attention.
Maggie on the other hand is extremely shy and easily pushed around by her sister. Her scars created an even more reclusive character over time. She sees the items that Dee wants as useful items, not things to show off to friends. She lives the life of poverty with her mother and knows that she has to work for what she has. Those quilts were promised to her and she will one day need them/use them for practical reasons. Taking the quilts with her one day, she sees her heritage as something that is passed down from her mother to her, and eventually to her children. It would never be something she'd put "on display" like art. She and her sister never had anything in common, nor will they. Their contrasting characteristics are what create the friction in this story.