Your toenail is keratin, the same protein as a horse's hoof. It is one of the most waterproof structures on your body and its only biological job is to keep things out. It does not know the difference between water and medicine. When you brush tea tree oil onto a toenail, roughly 5% gets through. The other 95% sits on the surface, evaporates, and comes off inside your sock.
FungiClear contains oregano oil, which is rich in carvacrol and thymol. These compounds act as biological solvents, loosening the dense keratin structure and opening channels down through the nail plate. Once that barrier is open, the antifungal finally reaches the nail bed where the infection actually lives, instead of drying on top of a wall it was never built to cross.