Repurchase/restocking loyalty
A very large share of reviewers explicitly state this is their 2nd, 3rd, or 4th+ repurchase, often keeping it stocked at home as a go-to hydration mask.
Brand trust in ROUND LAB
Many buyers cite general trust in the ROUND LAB brand and its birch juice line, having had good experiences with other products in the range (toner, cream, cleansing foam) before buying the mask.
Sale/promotion and value pricing
Numerous reviews mention buying because it was on sale, part of a bundle/promotion, or because the 10-pack offers strong cost-per-use value compared to pricier competitor masks.
Travel discovery in Korea
Several Japanese and other international reviewers discovered the product while traveling in Korea and now repurchase it via online retailers since it's hard to find locally.
Suitability for sensitive/dry skin
Buyers with sensitive, dry, or fragrance-averse skin purchased it specifically because it is described as fragrance-free, gentle, and non-irritating.