Everyone's lips have a natural color, and some people's lips are more pigmented than others. Because of your natural lip color, your lipstick color may look different when applied to your lips. This is especially true if the color is more on the transparent side - aka a sheer or creamy finish. A matte finish is typically more opaque, so it will do a better job at covering your natural lip color.
@buffalobeautyboy shared some of his Color Theory in his recent YouTube video where he adds yellow into his Custom Lipstick to balance out his natural lip's mauve color.
