Hello. Thank you for posting today.
I can't say why only one of your nails is like this and not the others. That is an oddity! Were the others ever smooth/glossy? Or it's always been only one? Generally, smooth, shiny fingernails are a sign of good nail health. Nails are made up of a protein called keratin that can be damaged over time by injuries, malnutrition and regular exposure to chemicals in nail products, dishwashing soaps and bleach.