Build makeup involves creating or assembling makeup products, usually from individual ingredients or components. This process can include mixing pigments, oils, and other substances to create a final product like lipstick, foundation, or eyeshadow. Companies may do this to produce unique colors, textures, or formulas that aren't available in pre-made products. It's similar to crafting your own recipe, where you control what goes into the product. Some people or businesses may do build makeup to customize products to match specific skin tones, preferences, or needs, giving them a personalized beauty experience.