Repeat/loyal purchase
A very high share of reviews explicitly mention this is their 2nd-5th+ repurchase, describing it as a staple they can't be without, especially compared to other d'Alba tone-up shades (pink/green).
Word-of-mouth / social media hype
Several buyers say they purchased after seeing SNS posts, influencer recommendations, or general online buzz ('話題だったので購入しました', 'SNSでおすすめしている投稿を見て購入').
Value of twin/duo set pricing
Many reviewers highlight that the 2-piece 'duo' set felt like great value or was cheaper than buying single bottles, driving the purchase decision (e.g. '1+1でお得', 'Set 2 kem chống nắng giá siêu hời').
Switching from the pink variant
A notable subset bought the purple version after already using d'Alba pink, seeking stronger tone-up or a better match for yellow-toned/oily-in-summer skin.
Ingredient/formula reputation for sensitive or dry skin
Buyers with dry or sensitive skin specifically chose this because previous sunscreens caused irritation or dryness, and they'd heard this one was gentler and more moisturizing.