www.elitefourum.com/t/a-guide-explaining-why-no-rarity-comes-from-packs-and-decks/16617/1
This is a great post on no rarity. Basically, the first wave of base set in Japan in 1996 came without rarity symbols because there was no intention to denote rarity, but this decision was changed and later print runs included the rarity symbols we’re used to now. The significance of no rarity base set is that it’s the very first wave of the Pokemon TCG as we know and love it in any language. Despite that, no rarity cards tend to fetch a fraction of the price that English 1st edition cards do.