The answer to this question is : the Writer's craft
Where is the story for this?
The most positive is gonna be thrifty
Hermia loves Lysander, but Hermia's perspective would be to marry Demetrius for he is her only escape from death and from spending her life in the convent. Though Lysander and Demetrius are equal in all measures, the only difference is that Demetrius has the permission from her father to marry her.