Every program is different and they're looking for different people every year. The way I've heard it best described is the faculty are curating their MFA students, so not only do they look at your work but also they consider you and how your work/personality would fit into their image of the program that year in combo with the work of those already in the program and the other applicants they are considering for interviews. Don't feel bad. & getting an interview at Yale is dope