Ingredient reputation (glutathione + niacinamide)
Many buyers cite the combination of glutathione and high-percentage niacinamide as the main draw, expecting brightening and antioxidant benefits.
Affordable price / sale promotions
Numerous reviewers mention buying because it was on sale or very cheap for the ingredient concentration, calling it high value for money.
Repeat purchase / loyalty
A large number of reviews are 2nd-7th repurchases, with some buyers stocking multiple bottles for themselves and family.
Sensitive skin compatibility
Buyers with sensitive or acne-prone skin specifically chose this over other niacinamide serums because it reportedly does not irritate or cause breakouts.
Line/brand extension
Some purchased after trying APLB sheet masks, toner, or body lotion and wanted to complete the skincare line for a synergy effect.