What does it mean to talk about the “shape of life”? Are some lives better than other simply in virtue of their “shape”?. Religious Studies

The “shape of life” states that if a person's life has the same amount of happiness and un­happiness (regardless of what came first) equates the well-being of said person. From what I understand, this view basically states that a person who has a very happy life at the begin­ning that later starts getting worse (going from a good shape to a bad shape), has had an equal existence to those who had a very unhappy life at the beginning and then improves (going from a bad shape to a good shape). I don't necessarily agree with this; I think im­proving always brings more happiness than deteriorating, so a life that is shaped like an as­cending line seems better to me.