Your under-eye skin naturally thins over time. Blood vessels become more visible through this delicate tissue. This creates that persistent bluish tone that concealer struggles to cover completely. 

The supportive fat pads beneath your eyes gradually shift and diminish. This creates hollows where fullness once existed. Shadows form in these recessed areas  regardless of skin color. 

Sun exposure, rubbing, and genetic factors contribute to actual color changes in the skin itself. This true pigmentation requires different approaches than shadow-based darkness. 

Fluid movement becomes less efficient with age. Mild swelling can develop. This creates additional shadowing and compounds existing concerns in the under-eye area.

The natural changes in your cheek and orbital bones create new contours. These affect how light reflects across your entire mid-face. Addressing these structural relationships becomes essential for complete improvement.