the.com/rarity

means Something uncommon enough that its scarcity alone makes people want it, regardless of actual quality.

from From Latin 'raritas,' rooted in 'rarus' meaning thin, sparse, or widely spaced — originally describing things with loose, scattered texture, like a thinly woven cloth, before it drifted into meaning 'scarce' or 'few in number.' The same 'rarus' gives English 'rare.' Essentially, the word started out describing gaps in fabric and ended up describing gaps in supply.