I think it depends on what the purpose is for the secret. On one of the scale you have secrets which amount to be socially appropriate, and on the other end of the scale are secrets which reflect only on your own selfishness and lack of caring for others. There are temporary secrets such as waiting to surprise someone with a big birthday present.

Secrets are always in a complex social context. Anyone who could keep no secrets and simply blurted out everything they knew to everyone would quickly become a social outcast.