Edge case is a classic engineering term for scenarios that are considered extreme, rather than typical. It might make sense to avoid edge cases when you’re adding features: software that includes every “wouldn’t it be nice if . . . ?” scenario that anyone has ever thought of quickly becomes bloated and harder to use. But when applied to people and their identities, rather than to a product’s features, the term “edge case” is problematic—because it assumes there’s such a thing as an “average” user in the first place.
