YesStyle and Skin Cupid are almost the same store.

Channel count treats every shelf as a separate win. Overlap data asks a harder question: which of these shelves are actually the same shelf?

The tightest pair on our charts is YesStyle and Skin Cupid — 20 shared brands, 59% of the smaller shelf. Next is YesStyle and iHerb at 16 shared, then Olive Young Korea and YesStyle at 14.

The specialists are one cluster, not four

The pattern is not random. The heaviest overlaps sit among the K-beauty specialist retailers — YesStyle, Skin Cupid, iHerb — which are chasing the same shopper: someone who already knows the category and is choosing between known brands.

For a brand, that means adding your third specialist is worth much less than the count suggests. You are largely re-reaching a customer who could already find you. The channel number goes up; the addressable audience barely moves.

What a genuinely new channel looks like

The opposite case is a pair with almost no overlap — a prestige or mass shelf against a specialist one. Those are the crossings that add a customer who was not previously reachable, and they are also the hardest gates. Our prestige data makes the point bluntly: Sephora and Ulta, both US prestige, share exactly one Korean brand.

Which reframes 29% — the share of brands on more than one channel at all. That figure is not just "most brands are narrow." It is that even the ones who expand often expand sideways, into an adjacent shelf serving the same person.

What we'll watch next

Once the archive has depth we can order these crossings in time — whether specialists reliably precede prestige, and whether any channel functions as a genuine gateway rather than a mirror of the one next to it. Right now we can only show the mirrors.