One way of achieving perennial consistency is to design future-proof URLs. For example, if we're building a social network where every user must belong to an organization, we can identify a user with a URL structure similar to /orgs/<org-id>/users/<user-id>. But if we think ahead, there may be a time in the future where our platform needs to cater for users belonging to multiple organizations; in that case, the URL structure we proposed would not support this.

Therefore, we should design our URL to simply include the user's ID (that is, /users/<user-id>). Then, to associate a user with an organization, we can implement the concept of membership, and structure the membership URL to have the structure /orgs/<org-id>/members/<member-id>.