Every time your skin reacts to sun exposure, an ingredient, even just friction, it triggers an internal alarm deep beneath the surface telling your pigment cells to produce more color.
And even after the reaction is completely over, that alarm stays on.
This is called the Melanin Loop, and it's the reason your spots keep surviving everything your routine throws at them.
SPF can't silence it, Vitamin C can't reach it, and exfoliators can't scrape it away.
Not because they're weak, but because they were never designed to go where the Melanin Loop lives.